Cisco Catalyst 4500 Series Software Configuration Guide

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.8.0E and IOS 15.2(4)E
Chapter 61 DHCPv6 Options Support
Information About DHCPv6 Options Support
To maintain interoperability with existing DHCP relays and servers, LDRA implements the same
message types (RELAY-FORWARD and RELAY-REPLY) as a DHCPv6 relay agent. LDRA allows
relay-agent information to be inserted by an access node that performs a link-layer bridging (that is,
non-routing) function. The LDRA resides on the same IPv6 link as the client and a DHCPv6 relay agent
or server.
LDRA for VLANs and Interfaces
You can configure LDRA on VLANs and interfaces. LDRA is not enabled by default. You must enable
it on the VLAN or interface first.
In a typical deployment, a majority of the interfaces or ports on a device are client facing. In such a
scenario, you can configure LDRA functionality on the VLAN. When you configure LDRA on a VLAN,
the functionality is configured on all ports or interfaces within the VLAN. Instead of configuring LDRA
functionality individually on interfaces and ports within a VLAN, you can configure LDRA on the entire
VLAN. As a result, all ports or interfaces associated with the VLAN will be configured as client facing.
You can also configure LDRA functionality on a specific interface or port. An interface or port can be
configured as client-facing trusted, client-facing untrusted, or server facing.
The LDRA configuration on a VLAN has to be configured as trusted or untrusted. An LDRA must
implement a configuration setting for all client-facing interfaces, marking them as trusted or as
untrusted.
By default, any interface that is configured as client facing will be configured as an untrusted interface.
When a client-facing interface is deemed untrusted, LDRA will discard any message of type
RELAY-FORWARD received from the client-facing interface.
CAPWAP Access Controller DHCPv6 Option
The Control And Provisioning of Wireless Access Points (CAPWAP) protocol allows lightweight access
points to use DHCPv6 to discover a Wireless Controller to which it can connect. CAPWAP is a standard,
interoperable protocol that enables a controller to manage a collection of wireless access points.
Wireless access points use the DHCPv6 option 52 (RFC 5417) to supply the IPv6 management interface
addresses of the primary, secondary, and tertiary Wireless Controllers.
Both stateless and stateful DHCPv6 addressing modes are supported. In stateless mode, access points
obtain IPv6 address using the Stateless Address AutoConfiguration (SLAAC), while additional network
information (not obtained from router advertisements) is obtained from a DHCPv6 server. In stateful
mode, access points obtain both IPv6 addressing and additional network information exclusively from
the DHCPv6 server. In both modes, a DHCPv6 server is required to provide option 52 if Wireless
Controller discovery using DHCPv6 is required.

Cisco Catalyst 4500 Series Specifications

General

Series	Catalyst 4500 Series
Category	Switch
Layer Support	Layer 2, Layer 3
Form Factor	Modular chassis
Stackable	No
Chassis Slots	3, 6, 7, 10
Power Supply Options	AC, DC
Redundancy	Power supply, Supervisor engine
Network Management	Cisco IOS Software CLI, SNMP, Cisco Prime Infrastructure
Features	Security, QoS
Port Density	Up to 384 ports per chassis
Security Features	802.1X, ACLs, DHCP Snooping, Dynamic ARP Inspection, IP Source Guard
Supervisor Engine	8-E