Posts Tagged ‘ port

STP & Layer 2 Switch redundency 30 June 2008 at 12:17 pm by admin

Bitmindframes Study guides

Spanning Tree Protocol & Layer 2 Redundency.

Layer 2 redundency improves network availability with alternative network paths.
A simple path can be disrupted with little impact.
Redundency is achieved at the distribution & core through additional hardware & alternate paths.
Each Access Layer switch is connected to 2 different Distribution Layer switches.
Each Distribution Layer switch is connected to 2 Core Layer switches.
Spanning Tree Protocol is enabled by default.
Spanning Tree Protocol puts some ports into forwarding & others in blocking.
This prevents Layer 2 switching loops. Spanning Tree Protocol uses a redundant link if the primary fails.

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Tags: vtp, cisco, switch, router, ip, guides

+ Cisco DTP Dynamic Trunking Protocol By admin 27 June 2008 at 12:24 pm and have 1 Comment

Bitmndframes cisco study guides

DTP Dynamic Trunking Protocol

Trunk negotiation is managed by the Dynamic Trunking Protocol (DTP), which is a Cisco proprietary Point-to-Point Protocol.
These various modes are configured using the switchport mode interface command
Switch trunk interfaces support different trunking modes.

  • Access
  • Dynamic desirable (default mode on Catalyst 2950 and 3550)
  • Dynamic auto
  • Trunk
  • Non-negotiate
  • dotq-tunnel (Not an option on the Catalyst 2950.)

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Tags: wan, cisco, switch, vtp, 802.1q, ip

+ VTP VLAN trunking protocol By admin 23 June 2008 at 4:23 pm and have 2 Comments

Bitmindframes study guides

What is VTP?

VLAN Trunking Protocol (VTP) is a Cisco proprietary Layer 2 messaging protocol that manages the addition, deletion, and renaming of VLANs on a network-wide basis. Virtual Local Area Network (VLAN) Trunk Protocol (VTP) reduces administration in a switched network. When you configure a new VLAN on one VTP server, the VLAN is distributed through all switches in the domain. This reduces the need to configure the same VLAN everywhere. To do this VTP carries VLAN information to all the switches in a VTP domain. VTP advertisements can be sent over ISL, 802.1q, IEEE 802.10 and LANE trunks. VTP traffic is sent over the management VLAN (VLAN1), so all VLAN trunks must be configured to pass VLAN1. VTP is available on most of the Cisco Catalyst Family products.

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Tags: ip, guides, interface, switch, wan, router

+ Configuring switch security for cisco catalyst 2950 By admin 18 June 2008 at 5:25 pm and have 1 Comment


Configuring port security

A switch without port security allows attackers to connect to unused, ports and gather info or attack the network. All ports should be secured before a switch is deployed. Port security limits the number of MAC addresses allowed on port.
If you limit the number to 1 & assign a single MAC address only the pc attached is allowed to connect via that port, when that number is reached a security violation occurs.

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