4000310515centerDate3300095000Date420003263900175001760220 450000 25527005665061 ASSIGNMENT NO: ONE SUBMITTED TO: DR.M SHAFIQ SUBMIITED BY: IQRA MUBEEN (16451556-046) SECTION: BSIT A00 ASSIGNMENT NO: ONE SUBMITTED TO: DR.M SHAFIQ SUBMIITED BY: IQRA MUBEEN (16451556-046) SECTION: BSIT AWhat is MPLS protocol. Explain its operation and evaluation with references?MPLS:Multiprotocol Label Switching (MPLS) is a type of data-carrying technique for high-performance telecommunications networks.
MPLS directs data from one network node to the next based on short path labels rather than long network addresses, avoiding complex lookups in a routing table. The labels identify virtual links (paths) between distant nodes rather than endpoints. MPLS can encapsulate packets of various network protocols, hence its name “multiprotocol”. MPLS supports a range of access technologies ATM, Frame Relay, and DSL.Role and Function:A number of different technologies were previously deployed with essentially identical goals, such as Frame Relay and ATM.
The header of the Frame Relay frame and the ATM cell refers to the virtual circuit that the frame or cell resides on. The similarity between Frame Relay, ATM, and MPLS is that at each hop throughout the network, the “label” value in the header is changed. This is different from the forwarding of IP packets.
1 It is highly possible that MPLS will completely replace these technologies in the future, thus aligning these technologies with current and future technology needs. 2In 1996 a group from Epsilon Networks proposed a “flow management protocol”. 3 Their “IP Switching” technology, which was defined only to work over ATM, did not achieve market dominance. Cisco Systems introduced a related proposal, not restricted to ATM transmission, called “Tag Switching”4 (with its Tag Distribution Protocol TDP 5).Operation:A 20-bit label value. A label with the value of 1 represents the router alert label.a 3-bit Traffic Class field for QoS (quality of service) priority and ECN (Explicit Congestion Notification).
Prior to 2009 this field was called EXP. 6Devices that function only as transit routers are similarly called P (Provider) routers. 7 The job of a P router is significantly easier than that of a PE router, so they can be less complex and may be more dependable because of this.Labels are distributed between LERs and LSRs using the Label Distribution Protocol (LDP). 8 LSRs in an MPLS network regularly exchange label and reachability information with each other using standardized procedures in order to build a complete picture of the network they can then use to forward packets.
The MPLS Header is added between the network layer header and link layer header of the OSI model. 9 This optimization is no longer that useful (like for initial rationales for MPLS – easier operations for the routers). Several MPLS services (including end-to-end QoS 10 management, and 6PE 11) imply to keep a label even between the penultimate and the last MPLS router, with a label disposition always done on the last MPLS router: the «Ultimate Hop Popping» (UHP)12 13. Some specific label values have been notably reserved 14 15 for this use:0: «explicit-null» for IPv42: «explicit-null» for IPv6Many customers are likely to migrate from Frame Relay to MPLS over IP or Ethernet within the next two years, which in many cases will reduce costs and improve manageability and performance of their wide area networks. 16References:1.
^ MPLS Fundamentals, By Luc De Ghein Nov 21, 2006 (ISBN 1-58705-197-4)2.^ Applied Data Communications (A Business-Oriented Approach) James E. Goldman & Phillip T. Rawles, 2004 (ISBN 0-471-34640-3)3.
^ P. Newman; et al. (May 1996). “Epsilon Flow Management Protocol Specification for IPv4”. RFC 1953.
IETF.4.^ Y. Rekhter et al.
, Tag switching architecture overview, Proc. IEEE 82 (December 1997), 1973–1983.5.^ “IETF – Tag Distribution Protocol (draft-doolan-tdp-spec-00)”. IETF.
September 1996.6.^ L. Anderson; R. Asati (February 2009), Multiprotocol Label Switching (MPLS) Label Stack Entry: “EXP” Field Renamed to “Traffic Class” Field, IETF7.^ a b E.
Rosen; Y. Rekhter (February 2006), RFC 4364: BGP/MPLS IP Virtual Private Networks (VPNs), IETF8.^ B.
Thomas; E. Gray (January 2001), RFC 3037: LDP Applicability, IETF9.^ Save call telecommunication consulting company Germany Save call – MPLS10.^ Doyle, Jeff.
“Understanding MPLS Explicit and Implicit Null Labels”. Network World. Retrieved 2018-03-13.11.^ “6PE FAQ: Why Does 6PE Use Two MPLS Labels in the Data Plane?”.
Cisco. Retrieved 2018-03-13.12.
^ Gregg., Schedule, (2008). Router security strategies: securing IP network traffic planes. Smith, David J. (Computer engineer).
Indianapolis, Ind.: Cisco Press. ISBN 1587053365. OCLC 297576680.13.
^ “Configuring Ultimate-Hop Popping for LSPs – Technical Documentation – Support – Juniper Networks”. www.juniper.net. Retrieved 2018-03-13.
14.^ Dino, Farinacci, Guy, Fedorkow, Alex, Conta, Yaakov, Rekhter, C., Rosen, Eric; Tony, Li, “MPLS Label Stack Encoding”. tools.ietf.org. Retrieved 2018-03-13.
15.^ <[email protected]>, Eric C. Rosen. “Removing a Restriction on the use of MPLS Explicit NULL”.
tools.ietf.org. Retrieved 2018-03-13. 16.^ “AT&T — Frame Relay and IP-Enabled Frame Relay Service (Product Advisor)”, Research and Markets, June 2007.