Cisco Systems 2955 specifications Management VLAN is VLAN1

Other default feature details for the Cisco Catalyst 2955 Switch include:

•Management VLAN is VLAN1

•VLAN Membership-Static access ports are in VLAN1

•VTP Management-VTP server mode

•Autonegotiation of port speed and duplex settings

Q. How does IGMP snooping operate in Cisco Catalyst 2955 switches?

A. IGMP snooping in the Cisco Catalyst 2955 resolves the typical undesirable behavior of a Layer 2 switch that floods multicast packets to all ports in the ingress VLAN. Instead, the Cisco Catalyst 2955 snoops for incoming IGMP requests and decides where the IP multicast members reside. Based on the multicast group membership information from the IGMP packet, the Cisco Catalyst 2955 sets up a forwarding table for that specific multicast group’s traffic. This setup allows the Cisco Catalyst 2955 to forward the IP multicast traffic of a specific group to only the ports that have active members of the group.

Q. What is multicast VLAN registration (MVR) and how does it relate to an IP multicast implementation?

A. In multi-VLAN networks, subscribers to a multicast group may exist in more than one VLAN. Because of the VLAN boundary restrictions in a network that consists of Layer 2 switches, it may be necessary to replicate the multicast data transmission to the same group in different VLANs, even if they are on the same physical network. This results in more bandwidth being consumed than is required for a single data stream to a group. MVR alleviates this problem by registering a common VLAN for the source and receivers of the multicast data. MVR defines two types of ports—source ports and receiver ports. Source ports are ports where the multicast data source is connected, and receiver ports are ports where subscribers are connected. MVR treats both of these types of ports as if they belong to the same VLAN for switching multicast stream for configured multicast address.

Q. Is IGMPv3 supported on the Cisco Catalyst 2955?

A.Yes.

Q.What is 802.1x and how can I implement it in my network?

A.802.1x is an IEEE standard that defines how devices should be authenticated when they are attached to LAN ports. In order to implement 802.1x, a RADIUS authentication server such as Cisco ACS Version 3.0 is needed.

Q.I have the existing Cisco Catalyst 2900 XL and 3500 XL switches that support Cisco Group Management Protocol. Will these devices interoperate with Cisco Catalyst 2955 switches, which support IGMP snooping?

A.Yes. The Cisco Catalyst 2955, which supports IGMP snooping, will fully interoperate with your existing Cisco Catalyst 2900 XL and 3500 XL products that support Cisco Group Management Protocol.

Q.What is the maximum number of multicast entries or groups allowed per Cisco Catalyst 2955 Switch?

A.The Cisco Catalyst 2955 switches support a maximum of 255 IP multicast groups and support both IGMPv1 and IGMPv2.

Q.What does the mrouter option under IGMP snooping do?

A.Multicast-capable router ports are added to the forwarding table for every IP multicast entry. The switch learns of such ports through one of these methods:

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