CUSTOMER_CODE
SMUDE
DIVISION_CODE
SMUDE
EVENT_CODE
JAN2016
ASSESSMENT_CODE MC0087_JAN2016
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
8067
QUESTION_TEXT
Explain the four layers of the DARPA model.
SCHEME OF
EVALUATION
The four layers of the DARPA model are application, transport, internet
and network interface.
i.Network interface layer: The Network interface layer sends TCP/IP
packets off the network medium.
ii.Internet layer: the internet layer responsibilities include addressing,
packaging and routing functions. The internet layer is analogous to the
network layer of the OSI model.
iii.Transport layer: The transport layer provides the application layer
with session and data gram communication services. the transport layer
encompasses the responsibilities of the OSI transport layer.
iv.Application layer: The application layer allows applications access
the services of the other layers and it defines the protocols that
applications use to exchange data.
(2.5 marks each)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
8069
QUESTION_TEXT
Explain various methods of Delivery Internetworking Protocols.
SCHEME OF
EVALUATION
i.Unicast: The majority of IP addresses refer to a single recipient; this is
called a unicast address. Unicast connections specify a one-to-one
relationship between a single source & a single destination.
ii.Broadcasting: Broadcast addresses are never valid as a source
addresses. They must specify the destination address.
iii.Multicasting: If an IP datagram is broadcast to a subnet, it is received
by every hoist on the uses the limited broadcast address to allow a
diskless workstation to contact a boot server.
iv.Any costing: Sometimes, the same IP services are provided by
different hosts.
(2.5 marks each)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
8071
QUESTION_TEXT
Describe various IP Routing Schemes.
i.Static routing
ii.Distance vector routing
iii.Link state routing
SCHEME OF EVALUATION
iv.Path vector routing
v.Hybrid routing
(2 marks each, with explanation)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
72558
QUESTION_TEXT
Define firewall concept. Explain four important examples of
firewalls.
SCHEME OF
EVALUATION
A Firewalls illustration (2 marks)
Packet filtering firewall (2 marks)
Dual homed gateway firewall (2 marks)
Screened host firewall (2 marks)
Screened subnet firewall (2 marks)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
117776
QUESTION_TEXT
Explain the steps involved in SMTP Mail transaction Flow
1.
The sender SMTP establishes a TCP connection with the
destination SMTP. (1 mark)
2.
The message is sent, to which the receiver will identify itself by
sending back its domain name.(1 mark)
SCHEME OF
EVALUATION
3.
The sender now initiates the start of a mail transaction by
sending a MAIL command to the receiver. (1 mark)
4.
The second step of the actual mail exchange consists of
providing the server SMTP with the destinations of the message.(1
mark)
5.
When all RCPT commands are sent, the sender issues a DATA
command to notify the receiver that the message contents will flow.(1
mark)
6.
The client now sends the data line by line ending with 5
character sequence <CRLF>.(1 mark)
7.
At this juncture, the client has several possible actions: (1 mark)
*
mark)
If client has no more messages to send, it can quit.(1
*
If client has no more messages to send, but ready to
receive, it can issue TURN command(1 mark).
*
If the sender has another message to send, repeat step 3
and sends MAIL command.(1 mark)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
117782
QUESTION_TEXT
Explain various types of firewalls employed in TCP/IP.
i.
ii.
SCHEME OF EVALUATION iii.
iv.
Packet filtering firewall (2.5 Marks)
Dual homed gateway firewall (2.5 Marks)
Screened host firewall (2.5 Marks)
Screened subnet firewall (2.5 Marks)