Label Distribution Protocol (LDP)


Label Distribution Protocol (LDP) is one of the label distribution protocols supported by DC-MPLS. DC-LDP provides a complete, scalable, and fault-tolerant source code implementation of LDP.

DC-LDP is designed for OEMs building MSPPs, Carrier Ethernet, enterprise switches, routers, mobile backhaul, or packet – optical transport devices, and provides a wide range of protocol extensions for VPN, VPWS and VPLS, including RFC2547 BGP/MPLS VPNs and PWE3 (Martini).

DC-LDP Features

LDP Protocol Function

The DC-LDP software product includes the following LDP protocol function.

  • RFC 5036
  • IPv4 and IPv6 support
  • Unnumbered interface
  • Support for all combinations of label management modes
    • Downstream Unsolicited and Downstream on Demand Label Advertisement
    • Liberal and Conservative Label Retention
    • Ordered and Independent Label Distribution
  • Targeted adjacencies
  • Loop Detection using both Hop Count and Path Vector
  • Layer 2 VPNs
    • PWE3 architecture (RFC 3985)
    • VPWS (Martini) (RFC 4447)
    • VPLS (RFC 4762)
  • Layer 3 VPNs
    • RFC 4364 extensions
  • LSP Ping
    • RFC 4379
  • Extensible for OEM specific requirements
    • Support for private objects and TLVs
    • Proprietary data transferred across external interfaces for OEM processing
    • Support for proprietary MIB extensions
    • Support for OEM specific authentication

Management and Integration

  • Pre-integrated and transactional CLI, NETCONF, WEB UI, SNMP, REST, and scripted management solutions available through pre-integration and partnership with Tail-f ConfD
  • High-level Yang models map directly to operator-familiar semantics
  • Easily integrated with proprietary management solutions via alternative low-level MIB interfaces
    • Support for all BGP v4 MIB tables defined in RFC 1657
    • Extensions based on the latest BGP v4 MIB draft (draft-ietf-idr-bgp4-mibv2)
    • Proprietary extensions to allow MIB-based configuration of BGP routing policies
  • High availability and fault tolerance in management of configuration information (when used with Configuration Safe Store)

Carrier Class Design

  • Scalability
    • Optimized mainline for very fast LSP establishment
    • Binary trees ensure scaling of O(ln(N)) with number of LSPs supported
    • No hard-coded limits to number of interfaces or LSPs supported
    • Designed to handle thousands of interfaces and millions of LSPs
    • Distribution of components onto multiple cards
  • Carrier class availability
    • RFC 3478 Graceful Restart
    • Availability and fault tolerance in management of configuration information possible with Configuration Safe Store
    • See High Availability for more details
  • Interoperability
    • Major vendors: interoperates with all major implementations, including Cisco and Juniper
    • UNH-IOL: successful testing of all aspects of DC-MPLS at UNH Interoperability Lab. See for details.
    • We assist customers in their own testing, either in their labs or at customer field trials
    • Guarantee: interoperability problems are treated as problems and fixed within the same schedules.