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318 Chapter 5: Network Protocols
Table 5-40 summarizes some of the features of TFTP and FTP.
Table 5-41 lists the various codes that the Cisco IOS ping command can supply.
Figure 5-40 shows the types of encapsulating Ethernet headers that are listed and described in
Table 5-42.
Table 5-40
Comparison of FTP and TFTP
FTP
TFTP
Uses TCP
Uses UDP
Uses robust control commands
Uses simple control commands
Sends data over a separate connection than
control commands
Uses no connections, since UDP
Requires more memory and programming effort
Requires less memory and programming effort
Is not supported as an application in IOS
Is supported as an application in IOS
Table 5-41
Explanation of the Codes the ping Command Receives in Response to Its ICMP Echo Request
ping Command Code
Explanation
!
ICMP Echo Reply received
.
Nothing received
U
ICMP unreachable (destination) received
N
ICMP unreachable (network) received
P
ICMP unreachable (port) received
Q
ICMP Source Quench received
M
ICMP "can't fragment" message received
?
Unknown packet received
ch05.fm Page 318 Monday, March 20, 2000 5:06 PM