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
8068
QUESTION_TEXT
Explain different characteristics of Internet Control Message Protocol
(ICMP).
SCHEME OF
EVALUATION
i.ICMP uses IP as through ICMP were a higher level protocol.
ii.ICMP is used to report errors, not to make IP reliable. Data grams
can still be undelivered by the higher level protocols using IP services.
iii.ICMP cannot be used to errors with ICMP messages.
iv.For fragmented datagram’s, ICMP messages are only sent about
errors with the first fragment.
v.ICMP messages are never sent in response to datagrams, with a
broad cost or a multicast destination address.(2 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
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
117779
QUESTION_TEXT
Describe the characteristics of TCP
i.
ii.
iii.
SCHEME OF EVALUATION iv.
v.
vi.
(Any 5,
Stream Data Transfer (2 Marks)
Reliability (2 Marks)
Flow control (2 Marks)
Multiplexing (2 Marks)
Logical connections (2 Marks)
Full duplex
5×2=10)
QUESTION_TYPE
DESCRIPTIVE_QUESTION
QUESTION_ID
117783
QUESTION_TEXT
Explain point-to-point protocol and ISDN.
SCHEME OF
EVALUATION
Point-to-Point Protocol(POP) is a network-specific standard protocol.
PPP has three main components:
a.
A method for encapsulating datagrams over serial links.
b.
A link control protocol(LCP)
c.
A family of Network Control Protocols(NCP) (5 marks)
ISDN(Integrated Services Digital Network)
The ISDN Basic Rate Interface (BRI) usually supports two B-channels
with a capacity of 64 kbps each, and a 16 kbps D-channel for control
information. (5 marks)