19-02-2011, 12:09 PM
[attachment=8834]
Voice over Multiprotocol Label switching
Challenges in IP network
Shortest path is followed in IP network
Load sharing is not possible
Congestion is created in IP network
Routing in network layer
Processing is slow and delay is more
SOLUTION TO THE PROBLEM ?
MPLS
• Multi protocol label switching
• Reduces excessive delay
• Instead of shortest follows suitable path on the basis of constraint
• Reduce packet loss
• Provide TE
• Provide QOS and VPN networking
• How it work
• MPLS architecture
• LSR
• LER
• LSP
• LDP
• FEC
MPLS header
• MPLS operates by defining a label called shim header
• MPLS header is 32 bits
• MPLS operation
• label creation and distribution
• Table creation
• LSP creation
• Label insertion/lookup table
• Packet forwarding
• Traffic engineering TE
• Important factor for TE
• TE in MPLS
• Constraint based routing CBR
• Tunneling in MPLS
Label creation
• There are three method used in label creation,
1. Topology- based method
2. Request- based method
3. Traffic -based method
• Topology based method: uses normal processing of routing protocol(e.g. OSPF ,BGP)
• Request based method: uses processing of request based control traffic( such as RSVP)
• Traffic based method: uses the reception of packet to trigger the assignment and distribution of label
Label distribution
• The various schemes are used for label exchange are as ,
1. LDP-maps unicast IP destination into labels
2. RSVP,CR-LDP – used for traffic engineering and resource reservation
3. Protocol independent multicast(PIM)- is used for multicast state label mapping
4. BGP- for external labels (VPN)
Table creation
• On receipt of label binding each LSR creates entries in the LIB
• The table will specify the mapping between a label and an FEC
• Mapping b/w the I/p port and I/p label and o/p port and o/p label
• Table are updated whenever renegotiation of the label binding occurs.
LSP creation
• Label switch path are set by the signaling protocols
LDP
RSVP
• LSP is unidirectional
• In MPLS domain there exist number of LSPs that originate at ingress router and traverses one or more core LSRs and terminate at Egress router.
Voice over Multiprotocol Label switching
Challenges in IP network
Shortest path is followed in IP network
Load sharing is not possible
Congestion is created in IP network
Routing in network layer
Processing is slow and delay is more
SOLUTION TO THE PROBLEM ?
MPLS
• Multi protocol label switching
• Reduces excessive delay
• Instead of shortest follows suitable path on the basis of constraint
• Reduce packet loss
• Provide TE
• Provide QOS and VPN networking
• How it work
• MPLS architecture
• LSR
• LER
• LSP
• LDP
• FEC
MPLS header
• MPLS operates by defining a label called shim header
• MPLS header is 32 bits
• MPLS operation
• label creation and distribution
• Table creation
• LSP creation
• Label insertion/lookup table
• Packet forwarding
• Traffic engineering TE
• Important factor for TE
• TE in MPLS
• Constraint based routing CBR
• Tunneling in MPLS
Label creation
• There are three method used in label creation,
1. Topology- based method
2. Request- based method
3. Traffic -based method
• Topology based method: uses normal processing of routing protocol(e.g. OSPF ,BGP)
• Request based method: uses processing of request based control traffic( such as RSVP)
• Traffic based method: uses the reception of packet to trigger the assignment and distribution of label
Label distribution
• The various schemes are used for label exchange are as ,
1. LDP-maps unicast IP destination into labels
2. RSVP,CR-LDP – used for traffic engineering and resource reservation
3. Protocol independent multicast(PIM)- is used for multicast state label mapping
4. BGP- for external labels (VPN)
Table creation
• On receipt of label binding each LSR creates entries in the LIB
• The table will specify the mapping between a label and an FEC
• Mapping b/w the I/p port and I/p label and o/p port and o/p label
• Table are updated whenever renegotiation of the label binding occurs.
LSP creation
• Label switch path are set by the signaling protocols
LDP
RSVP
• LSP is unidirectional
• In MPLS domain there exist number of LSPs that originate at ingress router and traverses one or more core LSRs and terminate at Egress router.