IPSEC

RFC 3715 - IPsec-Network Address Translation (NAT) Compatibility Requirements
RFC 3706 - A Traffic-Based Method of Detecting Dead Internet Key Exchange (IKE) Peers
RFC 3947 - Negotiation of NAT-Traversal in the IKE
RFC 3948 - UDP Encapsulation of IPsec ESP Packets

IPSEC VPN

VPN
RFC 2401 Security Architecture for the Internet Protocol
RFC 2411 IP Security Document Roadmap

Basic protocols
RFC 2402 IP Authentication Header
RFC 2406 IP Encapsulating Security Payload (ESP)

Key management
RFC 2367 PF_KEY Key Management API, Version 2
RFC 2407 The Internet IP Security Domain of Interpretation for ISAKMP
RFC 2408 Internet Security Association and Key Management Protocol
(ISAKMP)
RFC 2409 The Internet Key Exchange (IKE)
RFC 2412 The OAKLEY Key Determination Protocol

WAN

RFC 1990  The PPP Multilink Protocol
RFC 2427 - Multiprotocol Interconnect over Frame Relay
RFC 2570 (FRF.16) UNI/NNI Multilink Frame Relay Interworking Implementation Agreement

LAN

802.1D-2004 - Spanning Tree
802.1X      - Port Based Network Access Control
802.1Q      - Virtual LANs

Management

SSH V3 compliance
RFC 4250 RFC 4251
RFC 4252 RFC 4253
RFC 4254 RFC 4256
RFC 4335 RFC 4344
RFC 4345
RFC 4419: Diffie-Hellman Group Exchange for the Secure Shell (SSH) Transport Layer Protocol

Voice

RFC 2326 Real Time Streaming Protocol (RTSP)
RFC 2327 SDP: Session Description Protocol.
RFC 3261
RFC 2617
RFC 3262
RFC 3263
RFC 3265
RFC 2806
RFC 2976
RFC 3311
RFC 3313
RFC 3323
RFC 3326

RFC 3325
RFC 3327
RFC 3329
RFC 3361
RFC 3420
RFC 3428
RFC 3486
RFC 3515
RFC 3608
RFC 3680
RFC 3824

RFC 3840
RFC 3841
RFC 3842
RFC 3856
RFC 3857
RFC 3858
RFC 3891
RFC 3892
RFC 3903
RFC 4028
RFC 4566

RFC 2327
RFC 3264
RFC 3266
RFC 3312
RFC 3388
RFC 3407
RFC 3524
RFC 3556
RFC 3605
RFC 3890

SNMP Compliant to following RFCS

SNMPv1 is defined in RFC 1157.
SNMPv2c is defined in several RFC's. RFC 2578-2580, 3416-3418.
SNMPv3 is defined by several RFC's in RFC 2576, 3410-3415.

LAYER-2 protocols compliant to following RFCS

PPP
RFC 1661: PPP
RFC 1662: PPP in HDLC-like framing
RFC 1332: IPCP
RFC 1334: PAP
RFC 1994: CHAP
RFC 3748: EAP

Routing compliants to the following RFCS

RIP
RFC 1058 (RIPv1)
RFC 2453 (RIPv2)

OSPF
RFC 2328: OSPFv2
RFC 1587: OSPF NSSA Option
RFC 1583: OSPF
RFC 3509 : OSPF  

BGP-4
RFC 1771 BGP-4 Standard RFC
RFC 2858 Multiprotocol Extensions to BGP-4
RFC 2385 Protection of BGP Sessions via TCP MD5 Signature Option
RFC 2439 BGP Route Flap Damping
RFC 1997 BGP Communities Attribute
RFC 1965 Autonomous Confederations for BGP [obsoleted by rfc3065]
RFC 1745 BGP4/IDRP for IP – OSPF Interaction
RFC 1657 Definitions of Managed Objects for BGP-4 using SMIv2
RFC 2796 BGP Route Reflection An Alternative to full mesh IBGP
RFC 2842 Capabilities Advertisement with BGP-4 [obsoleted by rfc3392]

GRE

RFC 2784

VRRP Compliants to following RFCS

RFC 3768