Configuration of DVMRP over a UDL

1
Configuration of DVMRP over a UDL
Configuration of DVMRP over a UDL

• UDLR Working Group
• Salt Lake City, IETF 52 - December 11th 2001
• Céline BENASSY-FOCH / Yann GUINAMAND /
• Philippe CHARRON
• celine.benassy_at_space.alcatel.fr
• yann.guinamand_at_space.alcatel.fr
• philippe.charron_at_space.alcatel.fr

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DVMRP Configuration over a UDL
Network architecture
UDL
modem
Receiver
DVB-S Gateway Feed
LAN
PSTN/ RNIS
Access router
ISP network
Receiver
Multicast data server
LAN
GRE TUNNEL
GRE TUNNEL
Internet
MBONE
3
DVMRP Configuration / Active Mode

• Active Mode Configuration on Receiver
• Standard DVMRP implementation on Feed and
  Receivers
• Feed and Receivers are DVMRP neighbors
• Required a return channel up for exchange Probe
  and Route Report messages
• Each router a list of neighbor routers (Mrouted
  Max number is 64)
• Bandwidth used is proportional to the number of
  neighbor routers
• Scalability issue
• The Feed is the Designated Forwarder on the UDL
• The Feed must be the Designated Querier on the
  UDL
• Smallest IP_at_ on the UDL

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DVMRP Configuration / Passive Mode

• Passive Mode configuration on Receiver
• No standard implementation on Receiver
• To solve scalability issue of DVMRP over a UDL
• Passive Receivers
• No return channel link
• No multicast message sent to the Feed
• To avoid using a dial-up return channel link (PPP
  connection)
• Forwarding of multicast data from the UDL to the
  LAN
• No interactivity,
• Only reception of multicast traffic

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DVMRP Configuration / Passive Mode

• The Feed is a standard DVMRP Router
• Upon reception of a join to a multicast session
  on the UDL
• Multicast data will be sent to the UDL interface
• Feed UDL interface IP address 10.0.0.1
• multicast session IP address 239.1.2.3
• mtest j 239.1.2.3 10.0.0.1
• If ALL receivers are passive no neighbor DVMRP
  router
• Receivers will not send multicast data to the LAN
  interface
• The Feed does not send Route Report message to
  Receivers
• One Receiver must be active on the UDL
• To exchange Probe and Route Report messages via
  the UDL
• The Feed will be seen as the Upstream Router /
  Receiver
• All receivers will forward multicast data to
  their LAN interfaces

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DVMRP Configuration over a UDL

• To switch between Passive and Active mode
• By default receivers are configured in Passive
  mode
• Upon reception of a specific event, receivers
  switch to Active mode
• Configuration example
• aba0 Receiver UDL interface
• phyint aba0 one_way
• rl0 Receiver LAN interface
• phyint rl0 switch_uni_bi 239.255.1.1
• In case of a return channel link based on PPP
• This event sets up the PPP connection

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DVMRP Configuration over a UDL

• DVMRP Configuration and Multicast applications
• A UDL with one active receiver and other passive
  receivers
• Multicast push content
• Multicast File Transfer with a Reliable Multicast
  Transport protocol
• Active receiver will send ACK or NACK message via
  the GRE tunnel
• This mechanism prevents other receivers from
  sending the same message
• Multicast application with interactivity
• Teleteaching, Collaborative work
• One main multicast flow from the source to
  end-users
• Receivers could be passive
• End-Users could contribute to the session
• Receivers switch to active mode to forward
  multicast data
• Optimization of the use of Return channel links

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Other Network architectures

• Connectivity on the same LAN as the Feed

? The receiver connected on the same LAN as the
Feed has to be ACTIVE ? Feed must be the
Designated Forwarder on the UDL ? Cheapest
route between the LAN and the UDL ?
Configuration example fl0 Feed LAN
interface phyint fl0 metric 1 threshold 1
r1l0 Active Receiver LAN interface phyint rl10
metric 10 threshold 25
DVB-S Gateway Feed
UDL
PASSIVE Receiver
LAN
ACTIVE mode Receiver
Multicast data server
LAN
Internet
Access router
MBONE
9
Other Network architectures

• MBone Connectivity via the UDL and the LAN

? Feed must be the Designated Forwarder and
Querier on the UDL ? Smallest IP_at_ on the UDL ?
Cheapest route from LAN to UDL ? Multicast
traffic coming from receiver LAN interface will
not be forwarded via the GRE tunnel ? Not
optimal ? An infinity metric has to be assigned
on the Receiver LAN interface r1l0 Active
Receiver LAN interface phyint rl10
metric 32
DVB-S Gateway Feed
Multicast data server
UDL
ACTIVE Receiver
Multicast data server
LAN
MBONE
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Conclusion

• DVMRP configuration over a UDL
• To reduce
• The number of GRE tunnels between the Feed and
  Receivers
• Bandwidth used by multicast session on the GRE
  tunnel
• The configuration of DVMRP Receivers needs to be
  adapted
• Active mode (at least one)
• Enables Users connected to the LAN to interact
  and participate to multicast group session
• Passive mode
• Receives multicast content pushed on the UDL, no
  interactivity
• Transparent for End-Users and Application

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Conclusion / Evolutions

• Draft-ietf-udlr-dvmrp-conf V00 ? V01
• Sect. 2.4 New network architecture MBONE
  connectivity via 2 access points
• Fig. 5 links Feed-Recv1and Recv1-Recv2 have been
  removed
• Sect. 3.1.1 Reformulation of a requirement (the
  Feed must be the Designated Forwarder)
• Sect. 3.3 has been reformulated (DVMRP
  scalability issue and passive mode)
• Sect. 4.1 Details about benefits with a RMT
  protocol
• Sect. 4.2 Details about switching between passive
  and active mode
• Changes V01 ? V02
• New wording of the document for clarity
• Any Questions or Remarks ?