Transcript Midterm Review

Midterm Review
Chapter 1: Introduction
Chapter 2: Application Layer
Chapter 3: Transport Layer
Chapter 4: Network Layer (up to 4.4)
Chapter 1: Introduction
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Network edge: different types of access networks and
communication links
Network core: packet switching, circuit switching,
packet switching vs. circuit switching
Delay, loss and throughput: simple calculations using
the 4 types of delay, bandwidth, link capacity, packet
loss rate, and throughput
Protocol layers: rationale behind layering design, the
Internet 5-layer protocol stack, difference between
Internet and OSI protocol stacks, encapsulation
Chapter 2: Application Layer
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Basic concepts: what’s involved in creating a network
application, definition of process, client, server and socket,
how to address a process, client-server and P2P paradigms
Transport layer services: what transport layer services are
required by application layer, TCP vs. UDP services and their
suitability for different applications
Protocols: comparative study of HTTP, FTP, Email and DNS
(e.g., in-band/out-of-band, stateless/ stateful, pull/push), be
able to describe how each protocol operates (using key
components and their interactions), understand web caching,
understand where to use SMTP, POP3 and IMAP for Email,
understand the different level DNS servers, their
interactions, different types of DNS records and how to
insert a record into DNS, calculate file distribution time using
client-server and P2P. You’re NOT required to memorize the
message formats, commands and codes for these protocols
Chapter 3: Transport Layer
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Basic concepts: what transport layer does (including services
provided and not provided), definition of end-to-end
connection and segment, transport vs. network layer,
multiplexing and demultiplexing
UDP: services and uses, segment format, checksum calculation
Reliable data transfer: comparative study of stop-and-wait, goback-N, selective repeat and TCP, their operations, pros and
cons, performances.
TCP in detail: services and uses, segment format, definition
and use of sequence #, ACK, time-out and duplicate ACKs
(retransmission), sliding window, receive window (rwnd) and
congestion window (cwnd), how to set time-out with RTT, when
and how to perform retransmission, fast-retransmit, TCP flow
control and TCP congestion control, understand SYN flooding
and SYN cookies, understand general methods for congestion
control (end-end vs. network-assisted, open-loop vs. close-loop)
Chapter 4: Network Layer
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Basic concepts: network layer services, definition of
datagram and host-to-host connection, routing and
forwarding
Virtual circuit vs. datagram networks: their operations,
offered services, pros and cons
IPv4 addressing and NAT: be able to determine CIDR
subnet address, subnet mask, # bits needed for host
and subnet portion, max. # hosts supported, range of
host IP addresses, address aggregation, forwarding
based on routing table, understand the use, operation,
and limitation of NAT