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[JohnR]

----- CHapter 8

8: Individual Router Configuration Practice
8.1. Demonstrate the Ability to Fully Configure a Router from the CLI, for a Router Which Has Had Start-up Config Erased
Cold Boot Router
Ctrl + Break within 60 seconds
in 25xx routers in 16xx routers
o/r 0x2142 confreg 0x2142
i
n
enable
copy start run
config term
enable secret xxxxx
config register 0x2102
Crtl +Z
copy run start
reload
Chapter 9
9.1.1.1. List three components of the TCP/IP protocol stack.
The TCP/IP Protocol has the following components:
protocols to support ftp, e-mail, remote login, and other apps
reliable and unreliable transports
connectionless datagram (packet) delivery at the network layer
ICMP provides contrrol and message functions at the network layer
The TCP/IP suite was developed in conjunction with DARPA
TCP/IP compares closely with the lower layers of the OSI model
7 Application Application
6 Presentation Application
5 Session Application
4 Transport Transport
3 Network Internet
2 Data Link Network INterface
1 Physical Network INterface
TCP/IP info is transferred in a sequence of datagrams. One message may be transmitted as a series of datagrams that are reassembled into the message at the receiving location
TCP - connection oriented, reliable, flow control by sliding windows, reliabilty by providing sequence #s and ack, TCP resends anything that is not received and supplies a virtual circuit between end user apps...
UDP - connectionless and unreliable, although responsible for transmitting messages, no software checking. UDP provides speed because of low overhead, no acks
16bits | 16 | 32 | 32 | 4 | 6 | 6
Source Port | Dest Port | Seque # | Ack # | hlen | reserved | code bits
ACK# - next expected TCP octet
HLEN the # of 32 bit words in header
reserved - set to 0
code bits -= control functions (ie setup and termination of session)
windows - # of octets that the sender is willing to accept
checksum -
urgent pointer - indicates the end of urgent data
option = one currently defined : maximum TCP segment size
data - upper layer protocol data
port#s below 255 are for public apps // 255-1023 are assigned for marketable apps // 1023+ are unregulated
3way handshake / open connection
send SYN (seq=x)
receive SYN (seq=x)
Send SYN (seq=y,ack=x=1)
recieve SYN (seq=y,ack=x+1)
send ACK (ack=y+1)
receive ACK (ack=y+1)

UDP Segment format
16 bits | 16 | 16 | 16 | xxxxx
Source Port | Dest port | lenght | checksum | data
UDP: TFTP, SNMP, NFS, DNS
. Describe four network layer protocols from the TCP/IP stack.
IP-provides connectionless, best effort delivery routing of datagrams, not concerned with content
ICMP - provides control and messaging capabilities
ARP - determines data link layer for known IP addresses
RARP - determines netwrok addresses when datalink address is known
Diagram the IP Datagram.

|Diagram the IP Datagram.
4 | 4 | 8 | 16 | 16 | 3 | 13 | 8
vers | helen | type of service | total lenght | identification | Flags | frag offset | TTL