The router must disable Protocol Independent Multicast (PIM) on all interfaces that are not required to support multicast routing.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
SRG-NET-000019-RTR-000003	SRG-NET-000019-RTR-000003	SRG-NET-000019-RTR-000003_rule		Medium

Description
A scope zone is an instance for a connected region of a given scope. Zones of the same scope cannot overlap while zones of a smaller scope will fit completely within a zone of a larger scope. For example, Admin-local scope is smaller than Site-local scope, so the administratively configured boundary fits within the bounds of a site. According to RFC 4007 IPv6 Scoped Address Architecture (section 5), scope zones are also required to be "convex from a routing perspective". That is, packets routed within a zone must not pass through any links that are outside of the zone. This requirement forces each zone to be one contiguous island rather than a series of separate islands.

Description

A scope zone is an instance for a connected region of a given scope. Zones of the same scope cannot overlap while zones of a smaller scope will fit completely within a zone of a larger scope. For example, Admin-local scope is smaller than Site-local scope, so the administratively configured boundary fits within the bounds of a site. According to RFC 4007 IPv6 Scoped Address Architecture (section 5), scope zones are also required to be "convex from a routing perspective". That is, packets routed within a zone must not pass through any links that are outside of the zone. This requirement forces each zone to be one contiguous island rather than a series of separate islands.

STIG	Date
Router Security Requirements Guide	2013-07-30

Details

Check Text ( C-SRG-NET-000019-RTR-000003_chk )
If IPv4 or IPv6 multicast routing is enabled, verify all interfaces enabled for PIM are documented in the network's multicast topology diagram. Review the router configuration to determine if multicast routing is enabled and which interfaces are enabled for PIM. If an interface is not required to support multicast routing and it is enabled, this is a finding.

Fix Text (F-SRG-NET-000019-RTR-000003_fix)
Document all enabled interfaces for PIM in the network's multicast topology diagram. Disable support for PIM on interfaces that are not required to support it.