Monthly Archives: February 2011

Advanced STP: RSTP and MSTP

Rapid Spanning Tree Protocol IEEE 802.1w defines RSTP. Works based on 802.1d principal concept. BPDU version field set to 2. Root bridge is elected as in 802.1d Port Roles:

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STP: 802.1d and PVST

Traditional Spanning Tree Protocol: To avoid bridging loops in L2 network with redundant paths. Defined in IEEE 802.1d standard. Bridge Protocol Data Unit (BPDU)s’ are used to communicate among all switches(bridges). SRC MAC = Mac address of the port on … Continue reading

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Etherchannel: PAgP and LACP

Can bundle up to 8 interfaces to a port-channel. Maximum number of port-channels in C3560 can be 48.

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VLAN trunking protocol (VTP)

Reduce admin work by distributing VLAN information from VTP server to clients. Works only on trunk interface. Packets are sent either in ISL frames or IEEE802.1q frames. VTP packets are addressed to the destination MAC address: 01-00-0C-CC-CC-CC

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Cisco IOS Tree

Below link has good information about the IOS image numbering, available packages and naming process. http://www.cisco.com/web/about/security/intelligence/ios-ref.html

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Private VLAN: Concept and Cisco IOS/F10 configuration

Why we need private VLAN: All hosts in a single VLAN can communicate with each other via L2. There may be situations where we need hosts in a vlan shouldn’t communicate with each other in the same VLAN. Example: In … Continue reading

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