Tag Archives: SWITCH 300-115 1.2a

SWITCH 300-115 1.2 Configure and verify Layer 2 protocols

1.2.a CDP, LLDP

https://wiki.wireshark.org/LinkLayerDiscoveryProtocol

Typically, LLDP uses Ethernet as its “transport” protocol. The Ethernet type for LLDP is 0x88cc.

LLDP Data Units (LLDPDUs) are sent to the destination MAC address 01:80:c2:00:00:0e. This address is defined as the “LLDP_Multicast” address.

There are both mandatory and optional LLDP TLVs defined. All compliant LLDP Data Units (LLDPDUs) must contain at a minimum the following four mandated TLVs in the following order :

  • Chassis ID TLV (Type = 1)
  • Port ID TLV (Type = 2)
  • Time To Live TLV (Type = 3)
  • End of LLDPDU TLV (Type = 0)

lldp_cap01

If the LLDPDU includes optional TLVs they will be inserted between the Time To Live TLV and End of LLDPDU TLV.

Optional TLVs include the Basic set of TLVS and the aptoide app download Organizationally Specific TLVS.

Besides the four mandated TLVs listed above the Basic set of LLDP TLVs also includes:

  • Port Description TLV (Type = 4)
  • System Name TLV (Type = 5)
  • System Description TLV (Type = 6)
  • System Capabilities TLV (Type = 7)
  • Management Address TLV (Type = 8)

SWITCH 300-115: 1.2 Configure and verify Layer 2 protocols

1.2.a CDP, LLDP

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/release/12-2_55_se/configuration/guide/3750xscg/swcdp.html

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/release/12-2_55_se/configuration/guide/3750xscg/swlldp.html

 dls2(config)#lldp run
dls2(config)#do sh lldp

Global LLDP Information:
Status: ACTIVE
LLDP advertisements are sent every 30 seconds
LLDP hold time advertised is 120 seconds
LLDP interface reinitialisation delay is 2 seconds
dls2(config)#do sh lldp neigh
Capability codes:
(R) Router, (B) Bridge, (T) Telephone, (C) DOCSIS Cable Device
(W) WLAN Access Point, (P) Repeater, (S) Station, (O) Other

Device ID           Local Intf     Hold-time  Capability      Port ID
dls1                      Fa0/11         120            B               Fa0/11
dls1                      Fa0/12         120            B               Fa0/12

Total entries displayed: 2

dls2(config)#do sh lldp neigh detail
————————————————
Chassis id: 0016.479e.4500
Port id: Fa0/11
Port Description: FastEthernet0/11
System Name: dls1

System Description:
Cisco IOS Software, C3560 Software (C3560-IPSERVICESK9-M), Version 12.2(55)SE6, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2012 by Cisco Systems, Inc.
Compiled Mon 23-Jul-12 13:10 by prod_rel_team

Time remaining: 97 seconds
System Capabilities: B,R
Enabled Capabilities: B
Management Addresses:
IP: 10.1.1.101
Auto Negotiation – supported, enabled
Physical media capabilities:
100base-TX(FD)
100base-TX(HD)
10base-T(FD)
10base-T(HD)
Media Attachment Unit type: 16
Vlan ID: 1