# Determine the device is a router or switch given the Device IP via snmp

Discussion in 'Cisco' started by KuttapanPro@gmail.com, Nov 5, 2007.

1. ### Guest

I Have a Linksys Managed Switch and a Cisco router

Using SNMP protocol I am trying determine the device is a router or
switch and

Also which all layers are supported by the device?

Following methods are used .

Issue a get request for: "sysObjectId", "sysDescr", "sysServices",
"ipForwarding".

Here is my problem I am surprised by the output of "sysServices"

For Cisco router sysServices = 78

For Cisco router ipForwarding = 1

For Linksys switch sysServices = 2

For Linksys switch ipForwarding = 2

For For windows workstation sysServices = 76

My Linksys Switch is a Layer 2 Device

Then value Should be 3 = 2^ (1-1) + 2 ^(2-1)

For Computing sysServices value blow stated Equation is used

Note:
A value which indicates the set of services that this
entity may potentially offer. The value is a sum.
This sum initially takes the value zero. Then, for
each layer, L, in the range 1 through 7, that this node
performs transactions for, 2 raised to (L - 1) is added
to the sum. For example, a node which performs only
routing functions would have a value of 4 (2^(3-1)).
In contrast, a node which is a host offering application
services would have a value of 72 (2^(4-1) + 2^(7-1)).
Note that in the context of the Internet suite of
protocols, values should be calculated accordingly:
layer functionality
1 physical (e.g., repeaters)
3 internet (e.g., supports the IP)
4 end-to-end (e.g., supports the TCP)
7 applications (e.g., supports the SMTP)
For systems including OSI protocols, layers 5 and 6
may also be counted.

1.What are Possible values for sysServices ?
How the sysServices value computed by the vendors?