ProCurve Series 2300 and 2500 Switches Release Notes

188
Enhancements in Release F.02.02
CDP
have expired. (The hold time for any data entry in the switch’s CDP Neighbors table is configured in
the device transmitting the CDP packet, and cannot be controlled in the switch receiving the packet.)
The Series 2500 switches purge expired CDP neighbor entries every three seconds.
Non-CDP devices such as some hubs and other devices that do not have CDP capability are
transparent to CDP operation. (Other hubs are CDP-aware, but still forward CDP packets as if they
were transparent to CDP operation. See “CDP-Capable Hubs” on page 198.) However, an intervening
CDP-aware device that is CDP-disabled is not transparent. For example, in figure 87, the CDP
neighbor pairs are as follows: A/1, A/2, A/3, A/B, B/C. Note that "C" and "E" are not neighbors because
the intervening CDP-disabled switch "D" does not forward CDP packets; i.e. is not transparent to CDP
traffic. (For the same reason, switch "E" does not have any CDP neighbors.)
Figure 87. Example of Incoming CDP Packet Results
CDP Switch "A"
(CDP Running)
CDP Neighbor Table
Port | Data
-------|--------------------
1 | Host 1 data
1 | Host 2 data
1 | Host 3 data
2 | Switch "B" data
CDP Workstation "1"
(Host 1)
(CDP Running)
Non-CDP Device "X"
Such as a Non-CDP
Hub Switch
CDP Workstation "2"
(Host 2)
(CDP Running)
Non-CDP Device "Y"
Such as a Non-CDP
Hub or Switch
CDP Workstation "3"
(Host 3)
(CDP Running)
CDP Switch "B"
(CDP Running)
CDP Neighbor Table
Port | Data
-------|--------------------
1 | Switch "A" data
5 | Switch "C" data
No CDP data for Switch
"D" because it has dis-
abled CDP operation.
Port 1
Port 1
CDP
Switch "C"
(CDP Running)
CDP Neighbor Table
Port | Data
-------|--------------------
3 | Switch "B" data
Port 3
Port 7
CDP-Disabled
Switch "D"
(No CDP Neighbor Table)
This switch drops CDP packets.
CDP Switch "E"
(CDP Running)
CDP Neighbor Table
Empty-No CDP
Neighbors
Port 2
Port 3
Port 17
Port 1
"A", "1", "2", and "3" are CDP neighbors.
"A" and "B" are CDP neighbors.
"B" and "C" are CDP neighbors.
Because "D" is CDP-capable, but has
disabled CDP, it is not a CDP neighbor
to either "B" or "E".
Port 5