General Packet Radio Service (GPRS) and Personal
Digital Assistant (PDA) Devices
Programme
Sub-Prog /
Project
Prog. Director
Owner
Author
Version Date
NPFIT
Information
Governance
Mark Ferrar
Tim Davis
Graham Packwood
31/03/2006
DOCUMENT RECORD ID KEY
NPFIT-FNT-TO-IG-GPG-0007.01
Version
1.0
Status
APPROVED
General Packet Radio Service (GPRS) and Personal
Digital Assistant (PDA) Devices:
Good Practice Guidelines
© Crown Copyright 2005
Page 1 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
Amendment History:
Version
0.1
0.2
1.0
Date
02/09/2005
03/03/2006
31/03/2006
Amendment History
First draft for comment
Technical Author
Approved
Forecast Changes:
Anticipated Change
Annual Review
When
March 2007
Reviewers:
This document must be reviewed by the following.
delegation for sign off.
Name
Malcolm
McKeating
Tim Davis
Signature
Title / Responsibility
IG Security Team
Manager
Head of Information
Governance
Indicate any
Date
Version
1.0
1.0
Approvals:
This document requires the following approvals:
Name
Tim Davis
Signature
Mark Ferrar
© Crown Copyright 2005
Title / Responsibility
Head of Information
Governance
Director Of Technical
Infrastructure
Date
Version
1.0
1.0
Page 2 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
Distribution:
Information Governance website: http://nww.connectingforhealth.nhs.uk/
Document Status:
This is a controlled document.
This document version is only valid at the time it is retrieved from controlled
filestore, after which a new approved version will replace it.
On receipt of a new issue, please destroy all previous issues (unless a
specified earlier issue is baselined for use throughout the programme).
Related Documents:
Ref no Doc Reference Number
Title
1
NPFIT-SHR-QMS-PRP-0015 Glossary of Terms
Consolidated.doc
© Crown Copyright 2005
Version
12
Page 3 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
Contents
General Packet Radio Service (GPRS) and Personal Digital Assistant
(PDA) Devices: ...............................................................................................1
1 Introduction ................................................................................................5
Abstract.........................................................................................................5
1.1 Aims and Objectives ............................................................................5
1.2 Assumed Reader Knowledge...............................................................5
1.3 Background..........................................................................................6
1.4 Disclaimer ............................................................................................7
2
GPRS System: An Overview......................................................................8
2.1 Connecting to the GSM network using a Laptop..................................8
2.2 Data transfer rates ...............................................................................9
2.3 APN address........................................................................................9
2.4 Accessing your remote network ...........................................................9
2.5 Securing the Data ..............................................................................11
2.6 Encryption Levels...............................................................................13
2.7 Road map to getting connected .........................................................14
3
PDA devices ............................................................................................15
3.1 Overview ............................................................................................15
3.2 Corporate e-mail access ....................................................................16
3.3 Individual PDA / Blackberry user........................................................17
3.4 Approved systems .............................................................................17
4
Risk ..........................................................................................................17
4.1 Contingency Plans and Procedures ...................................................17
4.2 Example Risks ...................................................................................18
5
Summary..................................................................................................19
6
Appendix A. Extracts from BS7799-1:2002.............................................20
7
Appendix B. Microsoft Outlook via GPRS. Tips on data transfer. ..........22
7.1 Microsoft Outlook Online Working......................................................22
7.2 Offline Working ..................................................................................23
7.3 Calendar Functionality .......................................................................24
8
Send and Receive Email..........................................................................24
9
Tips for using a Mobile Web VPN ............................................................24
10
Glossary................................................................................................25
© Crown Copyright 2005
Page 4 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
1 Introduction
Abstract
This guide is for both technical and non-technical staff wishing to implement a
General Packet Radio System (GPRS) data connection to a remote private
network, such as N3, via an existing mobile phone provider.
You will find information on:
•
Connecting laptops, mobile phones and Personal Digital Assistants
(PDAs) to N3.
•
The technology used to route data from a remote user into a private
network hosted by a Hospital, Trust or Internet Service Provider (ISP).
•
The benefits to NHS Clinical staff visiting patients at home, e.g.
accessing and amending records remotely.
1.1 Aims and Objectives
The following information provides a knowledge-based framework that will
help maintain best practice values in your own organisation. In using this
guide you will be conforming to best practice and therefore avoid some of the
potential consequences of non-compliance.
After completing this guide you should understand:
•
Good practice for organisations who wish to utilise GPRS technology in
a NHS or other healthcare environments.
•
The connection process and security requirements which should help
ensure confidentiality of data as it transits the Internet to the private
network.
1.2 Assumed Reader Knowledge
•
A basic familiarity with mobile technologies and information security.
•
Detailed technical knowledge is not required.
Further information on GPRS and related matters is available from the
Connecting for Health Information Governance website:
http://nww.connectingforhealth.nhs.uk/igsecurity/
HT
© Crown Copyright 2005
TH
Page 5 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
1.3 Background
GPRS is an ‘always on’ data transfer facility currently available from many
(GSM) mobile phone providers. The expansion of the existing mobile phone
infrastructure offers increased data transfer rates to and from a company
intranet via the wider internet community. Sometimes referred to as 2.5G (two
and a half generation), this is a bridging measure prior to a full network
upgrade to 3G (third generation) technology.
Prior to GPRS, data transfer was only available using the Short Message
Service (SMS) ‘text’ message’ service. This facility limited the amount of
transferable data to 160 characters, at a very low transfer rate of 9.6Kbps.
Figure 1 (below) shows the major components that make up a GSM/GPRS
network:
(Fig. 1: Overview of a Wireless Network. Courtesy of Texas Instruments. http://www.ti.com).
HT
TH
•
PSTN: Public Switched Telephone Network – the traditional, wired telephone
network. Copper wire carrying analogue voice data.
•
SGSN: Serving GPRS Support Node - responsible for the delivery of data packets,
from and to the mobile stations, within its geographical service area.
•
GGSN: Gateway GPRS support node - Interface (between the GPRS wireless data
network and other networks such as the Internet or private networks) that converts
the GPRS packets coming from the SGSN into the appropriate packet data protocol.
•
RNC: Radio Network Controller - The RNC carries out radio resource management,
some of the mobility management functions and is the point where encryption takes
place before sending user data to and from the mobile device.
•
BTS: Base Transceiver Station - A mobile phone base station that transmits and
receives signals to and from connected radio network controllers.
© Crown Copyright 2005
Page 6 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
1.4 Disclaimer
Reference to any specific commercial product, process or service by trade
name, trademark manufacturer, or otherwise, does not constitute or imply its
endorsement, recommendation, or favouring by NHS Connecting for Health.
The views and opinions of authors expressed within this document shall not
be used for advertising or product endorsement purposes. NHS Connecting
for Health shall also accept no responsibility for any errors or omissions
contained within this document. In particular, NHS Connecting for Health
shall not be liable for any loss or damage whatsoever, arising from the usage
of information contained in this document.
© Crown Copyright 2005
Page 7 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
2 GPRS System: An Overview
2.1 Connecting to the GSM network using a Laptop
Mobile phone vendors host GPRS data services. Remote mobile devices,
such as laptop PCs or PDAs, use these services to connect to a corporate or
PCT private network via the wider public Internet.
To utilise the GPRS service, you will require a removable GPRS card that
slots into the laptop PC. Smaller mobile devices such as PDAs have an
inbuilt solution. The exact type of laptop card will depend on the machine
used and the network provider.
A GPRS card, like a mobile phone, contains its own Subscriber Identity
Module (SIM) card and like a mobile phone, requires registration with the
vendor before use. Your vendor should provide suitable guidance on the
registration process. Fig. 2 (below) shows the typical design, size and
placement of a laptop GPRS/3G card:
(Fig. 2: GPRS card for laptop. Courtesy of Vodafone UK. www.vodafone.co.uk).
Together with the GPRS card the vendor should provide software which
controls the connection to the network. This may appear very similar to a
standard 56k Internet dial-up utility with dial in details and log on screen.
Fig. 3 (below) shows a typical example of a log on screen:
Fig. 3 : Example of a Vodafone GPRS log on utility. Details may vary from vendor to vendor.
© Crown Copyright 2005
Page 8 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
2.2 Data transfer rates
GPRS is a ‘data transfer only’ service. Different data rates are available for
‘uploading’ data (from mobile device) and ‘downloading’ data (to mobile
device). Data rates come in different sizes and permutations - referred to as
Classes. For example:
Class
Class 2 (2 + 1, 3)
Class 3 (3 + 1, 4)
Class 10 (4+1, 3 + 2)
Receive Data (Kbps)
26.8
40.2
171.2
Send Data (Kbps)
13.4
15.6
21.4
You should consider the type of GPRS applications or services you wish to
utilise via the network. This will help you to determine what transfer rate
best suits you needs.
Your service provider should be able to help with this calculation. Most
vendors charge for the amount of data you send and not for the time
connected to the network.
Please note that the funding of connection agreements is local and not made
through the national program
2.3 APN address
To enable the correct routing of your data, the service provider will allocate
you an Access Point Name (APN) address. The server at this address is
responsible for routing your data packets through the vendor network.
The type of service you subscribe to (e.g. Pay As You Go, Permanent) or the
package required (e.g. web access, email) will determine what connection
settings you will be provided with.
If you sign up for more than one service, you may possibly be required to
enter the APN details when you log on. Alternatively, the vendor may use one
internet address to route your traffic through their network which requires no
user input. Your Trust, hospital or COIN, if running a large account may have
a dedicated APN server.
Each SIM card must have the APN name registered against it. Your vendor
should do this during the registration process
2.4 Accessing your remote network
The purpose of using a GPRS enabled laptop PC is to have immediate
access to your company information: emails, files and folders or intranet.
GPRS alone provides the means to access these applications via the
combined GSM /Internet infrastructure or leased line. Provided your network
© Crown Copyright 2005
Page 9 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
will allow remote login and you remember your ‘credentials’, then access is
achievable.
Unfortunately, without any external access controls, or other security
measures, this type of working exposes a network to unacceptable threats
from hackers, unauthorised users and denial of service (DoS) attacks.
The GPRS user and the local NHS network provider have a responsibility to
put in place safeguards against such attacks. One such method is the use of
a Virtual Private Network (VPN). A VPN is a logical, ‘point-to-point’
connection or tunnel, between your mobile device and your remote network.
It is possible to configure the VPN to start from your laptop, or at your service
provider network. This path, once established maintains itself throughout the
session. See Figure 4 (below).
Fig. 4: A typical VPN setup.
A VPN can provide:
•
Remote user identity authentication.
•
Secure private transmission of data (no unauthorised listeners).
•
Verification of the integrity of data transmission.
We recommend a VPN session should commence from your laptop device
and end at your PCT/corporate network.
Your laptop will need VPN client software installed and configured. When
executed, this can establish a connection to your remote VPN network
server.
© Crown Copyright 2005
Page 10 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
2.5 Securing the Data
IP tunneling is central to implementing Mobile VPN (MVPN). In addition to
traditional wired VPN features, MVPN includes a set of mechanisms that use
dynamic IP tunneling to support user mobility.
IP tunnels are paths that IP packets follow while encapsulated within the
payload portion of another packet. These encapsulated packets are sent to
destination endpoints from originating endpoints via public (non-secure)
channels.
Tunnels can also exist at the link layer (similar to the Frame Relay model),
providing encapsulation for non-routable protocols, such as Layer 2 Tunneling
Protocol (L2TP) for Point-to-Point Protocol (PPP).
We do not recommend this over GPRS unless your patient data is
encrypted by other means.
There are two basic tunneling methods for implementing IP VPNs:
-
End-to-end or “voluntary”
-
Network-based or “compulsory”
2.5.1 End-to-end Tunnels
End-to-end, voluntary tunnelling technology is the preferred method for
supporting corporate based VPNs. The best example of this is IP Security
(IPSec).
An IPSec tunnel starts from a gateway server. It then matches security
parameters with client-software (distributed by the trust to its mobile users) on
the users PC. The VPN IPSec technology provides a secure tunnel that
extends from the remote clients laptop, via the GPRS backbone, across the
internet, to the gateway. The benefit of this model is the use of standard
TCP/IP protocol stack.
If authentication is successful, the user enters the corporate intranet to access
host computers and services. Voluntary IPSec tunnels include encryption of
all data. IPsec can provide packet encryption and authenticity using a sub-set
of protocols.
Due to this process placing added overhead (often more than 25%) on the
RF interface it is advisable to test your application(s) first before
undertaking a larger scale roll-out program.
© Crown Copyright 2005
Page 11 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
If implementing such a solution the Trust or hospital will need to include:
i.
GPRS enabled card for laptop PC.
ii.
Client software on users PCs to enable secure VPN connection.
iii.
A managed Authentication, Access and Accounting (AAA)
server. This would typically be a Remote Access Dial In User
Server (RADIUS).
2.5.2 Network-based tunnels
On the other hand, Network-based “compulsory tunnelling,” provides a more
favourable foundation for mobile VPN solutions.
This method is favoured as it assumes the wireless operator’s network
infrastructure itself features the intelligence and functionality necessary for
the deployment of mobile VPNs. It also presupposes that the air interface
owned by the wireless carriers is secure.
With “compulsory tunnelling,” network components such as access servers,
gateways, etc. (not the mobiles) initiate tunnels, which typically terminate at
the private network. If performance is an issue, then this may be an option.
DoH guidelines require the encryption of Patient Identifiable Data (PID)
under electronic transfer. This offers protection for data, as it flows over the
provider’s network, prior to entering the tunnel.
Application encryption such as TLS is the minimum expected standard.
Multiple subscribers can use compulsory tunnels. These can remain active
even if no subscriber transactions are in progress. This places fewer burdens
on the computing and routing infrastructure.
The compulsory approach to tunnelling also assumes the existence of
proper agreements between corporations or ISPs and wireless operators.
Service Level Agreements address the business relationships between
service providers and corporations, while the Security Associations (SAs)
or shared secrets used to generate IP Security session keys address the
technical relationships.
© Crown Copyright 2005
Page 12 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
2.5.3 Encryption
Encryption allows you to create secure connections over insecure channels.
Encrypting your network traffic provides two useful guarantees: privacy and
authentication:
•
The concept of information privacy is simple: the sending end encrypts
the information; this data then travels across the unsecured network.
The receiving end decrypts the information. This process keeps the
data private from someone snooping on the unsecured network.
•
Authentication is also a useful function. If the receiving system is
successfully able to decrypt the data, it knows the data must have
originated from the sending system, and not from a system in the
middle pretending to be the sender.
2.6 Encryption Levels
Encryption can take place at various levels during the transfer of data. The
most common levels are Application and Network:
2.6.1 Application-level encryption
A layer 7 security solution and provides a means of introducing encryption to
your data at a very high level, before it get processed for onward
transmission. Secure Socket Layer (SSL) and Transport Layer Security (TLS)
are similar flavours of an application security mechanism.
Application level encryption may be useful if your users only access a
single application to work in a secure manner. It is worth spending some
time establishing what will be transmitted whether applications and/or data.
DoH guidelines require the encryption of Patient Identifiable Data under
electronic transfer.
2.6.2 Network-level encryption
T
As previously mentioned, a VPN tunnel between the providers network, over
the Internet to the PCT /corporate LAN is an example of implementing
network-level encryption. Encryption of data does not occur until it enters the
tunnel.
For GPRS working with sensitive data, we do not recommend this model
and it is included here for reference only.
© Crown Copyright 2005
Page 13 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
2.7 Road map to getting connected
The following should help local IT support staff identify the steps necessary in
establishing a GPRS model for their Trust, Hospital or practice. 1
TPF
FPT
Make contact with a GSM provider and obtain information on the type(s) of
GPRS service available. To date, both Vodafone and Orange have provided
some form of GPRS solution to an NHS organisation. Other vendors should
also be able to provide a similar service.
Typical questions to ask might be:
1. Do you supply GPRS SIM cards for data transfer only?
2. Will you assign a single standalone APN server for our data
forwarding? (This may depend on traffic volume).
3. Do you provide software for laptop connection?
4. What kind of coverage do you have in our geographical area?
5. Can we link a laptop Media Access Control (MAC) address to the
registered SIM card?
6. Do you have any secure, VPN solutions available?
7. Do you have procedures to deal with lost or stolen GPRS cards? Can
you block the SIM card?
8. Will you assign fixed IP addresses for our users to route data via a
leased line or the Internet?
9. Will the Trust, Hospital or practice LAN will connect to the vendor’s
network via a leased line?
You should also:
•
Ensure that you have the necessary protection at the point this line
enters your network. A stand-alone Common Criteria EAL4 level
Firewall is required. Filter on I/Ps
•
Identify the service and application you wish to use. This may require
SSL / TLS encryption or the employment of a VPN solution for the
provision of forwarding Patient Identifiable Data.
1
Please note that these steps are not exhaustive, provide general guidance only and the actual process may vary
from provider to provider.
TP
PT
© Crown Copyright 2005
Page 14 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
At nodes of internet access the deployment of an Intrusion Detection
System (IDS) or Intrusion Prevention System (IPS) may be particularly
beneficial. Deployment should include branch sites such as GP surgeries
and health centres if they choose to utilise Internet connectivity rather than
N3.
To ensure that no element of the secure network architecture has been
overlooked a full penetration test performed by a CHECK-approved
tester should be undertaken. This needs to include testing of the VPN
infrastructure and any directly connected system.
Put in place procedures for dealing with a loss or theft of a laptop PC.
(See Section 4, following, for more information).
Further information is available within the Intrusion Detection Systems and
Intrusion Protection Systems: Good Practice Guidelines document.
3 PDA devices
3.1 Overview
Personal Digital Assistant (PDA) is the name for any small hand-held, mobile
device that provides computing as well as information storage and retrieval
capabilities for personal or business use. Often used for keeping calendars
and address book information close-to-hand they also known as a ‘handheld’.
GPRS services via a PDA handheld device, such as a BlackBerry, may
require intervention from an administrator for business use configuration. The
GPRS hardware is already part of the package when purchased. The
configuration of many newer PDA should handle 3G data transfer rates of
around 384Kbps and will fall-back to GPRS rates, should reception or network
coverage dictate. A GPRS enabled PDA will allow you to:
•
Access your email using Microsoft Outlook.
•
•
Browse the web via specially coded pages.
Transfer files.
•
Retrieve contact lists.
As with GSM/GPRS enabled devices, the PDA will contain a SIM card. To
use the PDA, you or your technical support area must first register the device
with your network provider. Not only will you need to register the unit for voice
calls, but additionally for GPRS services.
© Crown Copyright 2005
Page 15 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
E-mail is usually one of the most useful components of data transfer via a
PDA unit. The approach to the configuration of your hand held device is
different for corporate and individual users.
3.2 Corporate e-mail access
To access your corporate email – receive internal emails to your BlackBerry in
parallel with your outlook mail tool – you will need to have in place an
agreement for this service with your GPRS network provider.
Once this is established, the next step is to have your network mail server
talking to the BlackBerry network server. Your IT department must establish a
network connection between an internal exchange mail server and the
Blackberry server of your network provider.
To enable secure transfer of any mail traffic, the BlackBerry server will
generate encryption keys using the triple DES algorithm. The keys will be
distributed to both your mail server and the hand held device.
When sending mail to your corporate account, the mail server will: compress a
copy of the message, encrypt it using the generated key and forward it to your
PDA. On receipt of the message, the PDA device, using the same generated
key, will decrypt the message.
The process is the same, except in reverse, for any emails sent from your
PDA device. In order to access your corporate email, you must have an
account on the internal BlackBerry server (internal on your network). See
figure seven (below) which describes a user responding to an email using
their BlackBerry:
1. The user is sent an
email.
2. The email arrives at
the Exchange server and
is forwarded, as normal,
to the user's mailbox.
3. BlackBerry Enterprise
Server
automatically
compresses,
encrypts
and
forwards
the
message to the user's
handheld device.
4. Email is forwarded to
the handheld device via
the Internet and wireless
network.
5. The handheld device
receives decrypts and
decompresses the email.
Fig. Five: User Responds to email using the BlackBerry.
© Crown Copyright 2005
Page 16 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
3.3 Individual PDA / Blackberry user
As a non corporate user, when you purchase your PDA, you will register the
unit for voice, email and web services. The network provider should allocate
you an email address. The initial section of the address may be your name the second section is the address of the service provider’s mail server.
During the registration process, you are required to register a password which
enables access to your mail tool via the provider’s hosted web pages. This
web page has the tools required for setting up a mail redirection rule. The
redirection rule will allow you to have any mail sent to your BlackBerry/PDA
email account forwarded to your working mail tool.
Using your workplace Microsoft Outlook account (or similar mail tool), you can
set a reciprocal ‘mail redirection’ rule to forward copies of your email to your
BlackBerry/PDA device.
Unlike the corporate solution, there is no encryption applied by the network
provider.
If patient data is to be accessed guidelines state the mandatory use of
additional encryption to ensure confidentiality.
3.4 Approved systems
BlackBerry products are currently undergoing evaluation tests by the UK
Communications Electronics Security Group (UK CESG) organisation. This
government body provides security advice on network security and other
communications related products.
Following an evaluation, by CESG, on the encryption standard employed by
BlackBerry, a patch or configuration file will be forthcoming. This will
configure security parameters automatically.
It is likely that organisations wishing to employ the accredited security patch
will have to purchase this as an ‘add-on’ to existing systems from BlackBerry.
As yet there is no published timeframe stating when this will be available.
4 Risk
4.1 Contingency Plans and Procedures
N3 user organisations should draw up contingency plans to decide upon their
response to a laptop being lost, stolen, or otherwise compromised. In
© Crown Copyright 2005
Page 17 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
particular, how they might handle the possible embarrassment should the
compromise problem enter the public sphere.
As part of the contingency plan, organisations should prepare procedures
for when a user knows or suspects a laptop has been compromised, lost or
stolen.
4.2 Example Risks
There are multiple risks associated with mobile information sources and
multiple access points. The mobility and flexibility provided by GPRS
services, raises additional security concerns. For example:
•
Unauthorised export of information from a domain.
A wrongly
addressed email provides a gateway for data to transfer from a
laptop/GPRS connection to another system.
•
An attacker can subvert a laptop computer by modifying either the
hardware or the software. The computer will then probe, store and
then forward data to the agent.
•
Unauthorised persons view patient Identifiable Data (or other sensitive
NHS data) when a laptop is used in their presence or in a public place
(cybercafé / train).
•
A virus or other malicious code transfers itself from the laptop to the
host system.
•
The laptop hard disk, or removable storage media, is lost or stolen.
As stated in British Standards Institute publication (BS779-1:2002, Para. 9)
[1], “The protection required [for remote working...] should be
commensurate with the risks these specific ways of working cause. When
using mobile computing the risks of working in an unprotected environment
should be considered and appropriate protection applied. In the case of
teleworking the organisation should apply protection to the teleworking site
and ensure that suitable arrangements are in place for this way of
working”.
Appendix A includes further extracts from this document.
© Crown Copyright 2005
Page 18 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
5 Summary
GPRS data services offer mobile workers the means to remotely connect to a
private network, using the public communications infrastructure. Many of the
main GSM vendors offer GPRS services. Currently, there are no British
Telecom (BT) N3 catalogue items for GPRS. However, both Orange and
Vodafone currently have solutions in place for certain geographical areas.
If you are a mobile worker and require access to your Intranet to access or
transfer medium size files, then GPRS may be your solution. We strongly
recommend you employ some form of VPN technology and encryption to
secure any patient data.
To use the GPRS service:
•
Identify a suitable vendor.
•
Procure the hardware card and necessary software.
•
Obtain vendor details such as dial in and APN numbers.
•
Select the service and data rate you require.
•
Go through ‘road map’ bullet points / questions (Section 2.7, above).
•
Install VPN software on your mobile and remote server.
•
Ensure your data is secure.
•
Prepare a contingency plan for unplanned loss or theft.
Securing your data through encryption will incur overheads in terms of data
transfer speed. Many of the encryption schemes will ‘encapsulate’ your data
within additional frames.
Many server providers will ask you to employ encryption so that it does not
impact on their published transfer rates. Provided your applications do not
transfer vast amounts of data at any one time, this should not become a
problem.
GPRS coverage in all areas may not be available. You should check this
with your vendor.
Laptop and PDA working offers a robust and flexible solution for mobile
workers. However, it is vitally important to ensure that all data is secure
before commencing deployment.
© Crown Copyright 2005
Page 19 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
6 Appendix A. Extracts from BS7799-1:2002 2
Mobile computing and teleworking
Objective: To ensure information security when using mobile computing and
teleworking facilities.
The protection required should be commensurate with the risks these specific
ways of working cause. When using mobile computing the risks of working in
an unprotected environment should be considered and appropriate protection
applied.
In the case of teleworking the organisation should apply protection to the
teleworking site and ensure that suitable arrangement are in place for this way
of working.
Mobile computing
When using mobile computing facilities, e.g. notebooks, palmtops, laptops
and mobile phones, special care should be taken to ensure that business
information is not compromised.
A formal policy should be adopted that takes into account the risks of working
with mobile computing facilities, in particular in unprotected environments.
For example such a policy should include the requirements for physical
protection, access controls, cryptographic techniques, back-ups, and virus
protection. This policy should also include rules and advice on connecting
mobile facilities to networks and guidance on the use of these facilities in
public places.
Care should be taken when using mobile computing facilities in public places,
meeting rooms and other unprotected areas outside of the organisation’s
premises. Protection should be in place to avoid the unauthorised access to
or disclosure of the information stored and processed by these facilities, e.g.
using cryptographic techniques.
It is important that when such facilities are used in public places care is taken
to avoid the risk of overlooking by unauthorised persons. Procedures against
malicious software should be in place and be kept up to date. Equipment
should be available to enable the quick and easy back-up of information.
These back-ups should be given adequate protection against, e.g., theft or
loss of information.
Suitable protection should be given to the use of mobile facilities connected to
networks. Remote access to business information across public network
using mobile computing facilities should only take place after successful
identification and authentication, and with suitable access control mechanisms
in place.
2
For further information on BS 7799 see: http://www.bsi-uk.com/InformationSecurity/index.xalter
© Crown Copyright 2005
Page 20 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
Mobile computing facilities should also be physically protected against theft
especially when left, for example, in cars and other forms of transport, hotel
rooms, conference centres and meeting places.
Equipment carrying
important, sensitive and/or critical business information should not be left
unattended and, where possible, should be physically locked away, or special
locks should be used to secure the equipment.
Training should be arranged for staff using mobile computing to raise their
awareness on the additional risks resulting from this way of working and the
controls that should be implemented.
Teleworking
Teleworking uses communications technology to enable staff to work remotely
from a fixed location outside of their organisation.
Suitable protection of the teleworking site should be in place against, e.g., the
theft of equipment and information, the unauthorised disclosure of information,
unauthorised remote access to the organisation’s internal systems or misuse
of facilities. It is important that teleworking is both authorised and controlled
by management, and that suitable arrangements are in place for this way of
working.
Organisations should consider developing a policy, procedures and standards
to control teleworking activities.
Organisations should only authorise
teleworking activities if they are satisfied that appropriate security
arrangements and controls are in place and that these comply with the
organisation’s security policy. The following should be considered:
a) The existing physical security of the teleworking site, taking into
account the physical security of the building and the local environment.
b) The proposed teleworking environment.
c) The communications security requirements, taking into account the
need for remote access to the organisation’s internal systems, the
sensitivity of the information that will be accessed and pass over the
communication link and the sensitivity of the internal system.
d) The threat of unauthorised access to information or resources from
other people using the accommodation, e.g. family and friends.
The controls and arrangements to be considered include:
a) The provision of suitable equipment and storage furniture for the
teleworking activities.
b) A definition of the work permitted, the hours of work, the
classification of information that may be held and the internal systems
and services that the teleworker is authorised to access.
© Crown Copyright 2005
Page 21 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
c) The provision of suitable communication equipment, including
methods for securing remote access.
d) Physical security.
e) Rules and guidance on family and visitor access to equipment and
information.
f) The provision of hardware and software support and maintenance.
g) The procedures for back-up and business continuity.
h) Audit and security monitoring.
i) Revocation of authority, access rights and the return of equipment
when the teleworking activities cease.
7 Appendix B. Microsoft Outlook via GPRS. Tips on
data transfer.
7.1 Microsoft Outlook Online Working
The majority of people, who use Microsoft Outlook to access their email when
they are in the office, operate in online mode. When people work online,
Outlook maintains a ’live‘ connection to the server during the entire working
session.
People who access their email via a remote connection, using GPRS, and
who have tried to operate in online mode have almost certainly been subject
to a very different user experience:
•
Depending on the number of new emails that are available it can be
several minutes before the inbox is ’ready for inspection‘.
•
It can take a great deal of time to synchronise folders.
•
Sending and receiving emails with large attachments can be frustrating
because the Outlook client is unusable until the email has been sent or
received.
GPRS users should limit their online sessions to only those situations that
require them to create and edit rules, using the Out of Office Assistant and
editing offline settings.
© Crown Copyright 2005
Page 22 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
7.2 Offline Working
Offline is a more efficient way to work in dial-up situations, such as when the
GPRS bearer is being utilised. Working offline, users can take a single folder
or a subset of folders (e.g. calendar, contacts, deleted items, drafts, inbox,
journal, notes, outbox or sent items) from a server location and work with the
contents - without being connected to the network.
When users are ready to update the folders on the Exchange server with any
changes made offline, they ’synchronise‘ the two locations to make the
contents of both sets of folders identical.
Users may find it useful to configure Outlook so that the connection to the
server lasts just long enough to copy over any changes and disconnects
itself when this task is completed.
Only the offline changes users have made need copying across to the server
while newly received email messages (and all other all changes to information
on the server) will download to the user.
If users open one of these items in an offline folder, Outlook will not download
it again. Any deletion from either the offline folder or the corresponding server
folder applies to both folders. Once synchronisation is completed, Outlook
disconnects from the server and users work with the information in the offline
folders on their computer.
The following should help achieve the best offline performance:
•
Synchronise address book changes only. Address books may be very
large so it is not good practice to download the entire address book
each time a synchronisation action takes place. Outlook should be setup to download only the changes that have occurred since the previous
synchronisation.
•
Synchronise only the folders that are required.
Instead of
synchronising all folders configure Outlook to only process the
essential folders.
Using Microsoft Outlook 2000 it is possible to define which folders should be
synchronised.
The product provides a ’Mail and Calendar’ quick
synchronisation group as standard:
•
Use the Send/Receive option to send and receive new email.
•
Use the ’synchronise this folder’ option to synchronise the calendar
function. Select Tools and then Synchronise. Finally, click the This
Folder option.
All the ’standard‘ Microsoft folders (e.g. calendar, contacts, deleted items,
drafts, inbox, etc) can be synchronised by selecting the All Folders option
© Crown Copyright 2005
Page 23 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
under the Synchronise item. However, this method transfers much larger
amounts of data in comparison to only synchronising the sending and
receiving of email.
7.3 Calendar Functionality
It is possible to configure Microsoft Outlook to automatically synchronise the
calendar folder on a regular basis. This ensures the publicly viewable
calendar is up to date. It is also possible for the user to choose to
synchronise the calendar folder manually, as and when required.
8 Send and Receive Email
When people work offline it is likely that they will wish to send email messages
they have created and check for new emails from other people. In order to
send and receive email, users can select the Send/Receive option on the
mail client. Note that the status of messages (read or unread) may not be
updated in this case, so to avoid confusion it is always preferable to
synchronise the Inbox wherever possible.
Users may find the following information useful when sending and receiving
email:
•
Users can choose to synchronise individual folders, such as the inbox
or outbox, at any time by choosing ‘Synchronise this Folder’ on the mail
client. Select Tools and then the Synchronise option and then click
on the This Folder item.
•
Outlook can be particularly useful as it allows a user to configure
folders to synchronise, at regular intervals, without further user
intervention.
The amount of data that will be transferred during a full synchronisation is
dependent on how much work has been done since the last synchronisation
operation was performed e.g. how many e-mails have been received and
transferred, how many calendar updates have occurred etc. The figures
below give “a feel” for how much data will be transferred if nothing has
changed if Outlook 2000 is being used (e.g. if the client and server folders are
the same):
9 Tips for using a Mobile Web VPN
By its nature, a VPN solution will prevent any form of interference to the flow
of data in the interests of maintaining a high level of security. This is one of
the positive aspects of using a VPN.
© Crown Copyright 2005
Page 24 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
In the mobile world this can manifest itself as service disruption. If for
instance the GPRS connection is temporarily unavailable (e.g. train goes
through a tunnel), the VPN session may be dropped, as the VPN solution
perceives this to be a form of interference.
We therefore recommend that users keep this in mind when using the VPN while mobile.
10 Glossary
AAA:
Authentication, Access and Accounting. A framework for
configuring services that provide a secure network
connection and a record of user activity, by identifying
who the user is, what the user can access, and what
services and resources the user is consuming.
APN:
Access Point Name.
SGSN and GGSN.
BT:
British Telecommunications Plc is the current service
provider for the N3 network.
DoS:
Denial of Service attack.
An attack designed to
functionally cripple network functionality by flooding it with
useless traffic.
GSM:
Global System for Mobile Communications. The de-facto
wireless telephone standard in Europe.
GPRS:
General Packet Radio Service. A packet-based wireless
communication service promising data rates up to 115
Kbps and continuous connection to the Internet for mobile
phone and computer users. It is particularly suited for
sending and receiving small bursts of data, such as email
and web browsing, as well as large volumes of data.
IDS:
Intrusion Detection System.
An Intrusion Detection
System monitors any network traffic and logs/notifies any
possible malicious activity.
IPS:
Intrusion Prevention System. Any device which exercises
access control to protect computers from exploitation.
Intrusion prevention systems also have the ability to take
immediate action, based on a set of rules established by
the network administrator.
© Crown Copyright 2005
Provides routing information for
Page 25 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
IPSec:
Internet Protocol Security. A method of securing IP
communications for security that takes place at the
network or packet processing layer of network
communication.
ISP:
Internet Service Provider. A company that provides an
Internet connection
L2TP:
Layer 2 Tunnelling Protocol. A tunnelling protocol used to
support virtual private networks (VPNs).
MAC:
Media Access Control. A unique identifier used to
provide security for wireless networks. All Wi-Fi devices
have an individual MAC address hard-coded into it.
MVPN:
Mobile Virtual Private Network. VPN solution for mobile
devices.
PID:
Patient Identifiable Data. Key identifiable information
includes: patient’s name, address, full post code, date of
birth, pictures, photographs, videos, audio-tapes or other
images of patients. PID also encompasses NHS local
patient identifiable codes or anything else that could
identify a patient directly or indirectly. For example, rare
diseases, drug treatments or statistical analyses which
have very small numbers within small population may
allow the identification of individuals.
PDA:
Personal Digital Assistant. A handheld device that
combines computing, telephone/fax, Internet and
networking features.
PPP:
Point to Point Protocol. A data transfer protocol which
operates at the Data Link Layer.
RADIUS:
Remote Access Dial In User Server. An Authentication,
Authorization and Accounting (AAA) protocol that
enables remote access servers to communicate with a
central server to authenticate dial-in users and authorize
their access to the requested system or service.
SA:
Security Association. A relationship between two or more
entities that describes how they will utilise security
services to communicate securely
© Crown Copyright 2005
Page 26 of 27
GPRS and PDA Devices
NPFIT-FNT-TO-IG-GPG-0007.01
31/03/2006 / Approved / 1.0
SIM:
Subscriber Identity Module. The SIM card is the smart
card inserted inside all GSM phones that encrypts voice
and data transmissions and stores data about the specific
user so that the user can be identified and authenticated
to the network supplying the phone service. The SIM
also stores data such as personal phone settings specific
to the user and phone numbers.
SMS:
Short Message Service. A service for sending text based
messages of up to 160 characters.
SSL:
Secure Sockets Layer. A protocol designed to provide
secure communications across the Internet.
TLS:
Transport Layer Security. A protocol designed to provide
secure communications across the Internet designed as a
successor to SSL. It uses the same cryptographic
methods but supports more cryptographic algorithms.
UK CESG:
UK Communications Electronics Security Group. CESG
aims to protect and promote the vital interests of the UK
by providing advice and assistance on the security of
communications
and
electronic
data.
See
http://www.cesg.gov.uk/index.cfm for further details.
VPN:
Virtual Private Network. A private data network that
makes use of the public telecommunication infrastructure;
privacy is maintained through the use of a tunnelling
protocol and security procedures.
© Crown Copyright 2005
Page 27 of 27