Juniper JUNOSE 11.1.X MULTICAST ROUTING, Configuration Manual

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When enabled, the admission-bandwidth for a particular (S,G) is read from the
multicast bandwidth map and recorded in the mroute when the (S,G) mroute is
created. If you configure a port limit and the OIF count on the port exceeds that limit,
no OIFs on that port are added to mroutes (that is, OIFs are blocked).
When a multicast forwarding entry (an mroute) is added with an outgoing interface,
OIF is blocked from forwarding data if the additional bandwidth contributed by the
(S,G) would exceed the admission-bandwidth limit for the port on which the interface
resides.
CAUTION: Before you can limit port-level admission bandwidth, you must first create
a bandwidth map. See “Defining a Multicast Bandwidth Map” on page 10 for details.
Enabling Port Admission Bandwidth Control
You can use the mroute port admission-bandwidth-limit command to limit the
total multicast bandwidth that can be admitted on a port. The admitted bandwidth
is summed across all virtual routers with IPv4 and IPv6 mroutes that have OIFs on
the port.
NOTE: Admission bandwidth values for a given (S,G) mroute are determined from
the bandwidth map. See “Defining a Multicast Bandwidth Map” on page 10 for details.
Dynamic Port Admission Bandwidth Control
You can configure the system to dynamically limit the total multicast bandwidth that
can be admitted on a port. The system performs dynamic port-level admission control
when an OIF on that port is added to the mroute for a given <S, G> multicast
stream.
After the priority bandwidth limit on the port is reached, OIFs on the prioritized <S,
G> are only allowed to forward the traffic and unprioritized <S, G> streams are
blocked from forwarding data on the OIF.
To enable a priority value for the <S, G> multicast stream, issue “set priority” on
page 15 in the multicast bandwidth map. A priority value of 0 indicates an
unprioritized stream and any value other than 0 indicates a prioritized stream.
Currently there is no support for classification of prioritized streams. For more
information about the
set priority command, see “Defining a Multicast Bandwidth
Map” on page 10 .
You can configure limits for the bandwidth that is dynamically admitted on the port.
The priority bandwidth limit controls the priority bandwidth admitted on a port. The
hysteresis limit sets the minimum priority bandwidth limit before the system evaluates
mroutes and admits any blocked OIFs.
mroute port admission-bandwidth-limit
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Blocking and Limiting Multicast Traffic
JUNOSe 11.1.x Multicast Routing Configuration Guide