| 5201 | Host Identity ProtocolR. Moskowitz, P. Nikander, P. Jokela, Ed., T. Henderson · obsoleted by RFC 7401 | Experimental | April 2008 |
| 5202 | Using the Encapsulating Security Payload (ESP) Transport Format with the Host Identity Protocol (HIP)P. Jokela, R. Moskowitz, P. Nikander · obsoleted by RFC 7402 | Experimental | April 2008 |
| 5203 | Host Identity Protocol (HIP) Registration ExtensionJ. Laganier, T. Koponen, L. Eggert · obsoleted by RFC 8003 | Experimental | April 2008 |
| 5204 | Host Identity Protocol (HIP) Rendezvous ExtensionJ. Laganier, L. Eggert · obsoleted by RFC 8004 | Experimental | April 2008 |
| 5205 | Host Identity Protocol (HIP) Domain Name System (DNS) ExtensionsP. Nikander, J. Laganier · obsoleted by RFC 8005 | Experimental | April 2008 |
| 5206 | End-Host Mobility and Multihoming with the Host Identity ProtocolP. Nikander, T. Henderson, Ed., C. Vogt, J. Arkko · obsoleted by RFC 8046 | Experimental | April 2008 |
| 5207 | NAT and Firewall Traversal Issues of Host Identity Protocol (HIP) CommunicationM. Stiemerling, J. Quittek, L. Eggert | Informational | April 2008 |
| 5208 | Public-Key Cryptography Standards (PKCS) #8: Private-Key Information Syntax Specification Version 1.2B. Kaliski · obsoleted by RFC 5958 | Informational | May 2008 |
| 5209 | Network Endpoint Assessment (NEA): Overview and RequirementsP. Sangster, H. Khosravi, M. Mani, K. Narayan, J. Tardo | Informational | June 2008 |
| 5210 | A Source Address Validation Architecture (SAVA) Testbed and Deployment ExperienceJ. Wu, J. Bi, X. Li, G. Ren, K. Xu, M. Williams | Experimental | June 2008 |
| 5211 | An Internet Transition PlanJ. Curran | Informational | July 2008 |
| 5212 | Requirements for GMPLS-Based Multi-Region and Multi-Layer Networks (MRN/MLN)K. Shiomoto, D. Papadimitriou, JL. Le Roux, M. Vigoureux, D. Brungard | Informational | July 2008 |
| 5213 | Proxy Mobile IPv6S. Gundavelli, Ed., K. Leung, V. Devarapalli, K. Chowdhury, B. Patil | Proposed Standard | August 2008 |
| 5214 | Intra-Site Automatic Tunnel Addressing Protocol (ISATAP)F. Templin, T. Gleeson, D. Thaler | Informational | March 2008 |
| 5215 | RTP Payload Format for Vorbis Encoded AudioL. Barbato | Proposed Standard | August 2008 |
| 5216 | The EAP-TLS Authentication ProtocolD. Simon, B. Aboba, R. Hurst | Proposed Standard | March 2008 |
| 5217 | Memorandum for Multi-Domain Public Key Infrastructure InteroperabilityM. Shimaoka, Ed., N. Hastings, R. Nielsen | Informational | July 2008 |
| 5218 | What Makes for a Successful Protocol?D. Thaler, B. Aboba | Informational | July 2008 |
| 5219 | A More Loss-Tolerant RTP Payload Format for MP3 AudioR. Finlayson | Proposed Standard | February 2008 |
| 5220 | Problem Statement for Default Address Selection in Multi-Prefix Environments: Operational Issues of RFC 3484 Default RulesA. Matsumoto, T. Fujisaki, R. Hiromi, K. Kanayama | Informational | July 2008 |
| 5221 | Requirements for Address Selection MechanismsA. Matsumoto, T. Fujisaki, R. Hiromi, K. Kanayama | Informational | July 2008 |
| 5222 | LoST: A Location-to-Service Translation ProtocolT. Hardie, A. Newton, H. Schulzrinne, H. Tschofenig | Proposed Standard | August 2008 |
| 5223 | Discovering Location-to-Service Translation (LoST) Servers Using the Dynamic Host Configuration Protocol (DHCP)H. Schulzrinne, J. Polk, H. Tschofenig | Proposed Standard | August 2008 |
| 5224 | Diameter Policy Processing ApplicationM. Brenner | Informational | March 2008 |
| 5225 | RObust Header Compression Version 2 (ROHCv2): Profiles for RTP, UDP, IP, ESP and UDP-LiteG. Pelletier, K. Sandlund | Proposed Standard | April 2008 |
| 5226 | Guidelines for Writing an IANA Considerations Section in RFCsT. Narten, H. Alvestrand · obsoleted by RFC 8126 | Best Current Practice | May 2008 |
| 5227 | IPv4 Address Conflict DetectionS. Cheshire | Proposed Standard | July 2008 |
| 5228 | Sieve: An Email Filtering LanguageP. Guenther, Ed., T. Showalter, Ed. | Proposed Standard | January 2008 |
| 5229 | Sieve Email Filtering: Variables ExtensionK. Homme | Proposed Standard | January 2008 |
| 5230 | Sieve Email Filtering: Vacation ExtensionT. Showalter, N. Freed, Ed. | Proposed Standard | January 2008 |
| 5231 | Sieve Email Filtering: Relational ExtensionW. Segmuller, B. Leiba | Proposed Standard | January 2008 |
| 5232 | Sieve Email Filtering: Imap4flags ExtensionA. Melnikov | Proposed Standard | January 2008 |
| 5233 | Sieve Email Filtering: Subaddress ExtensionK. Murchison | Proposed Standard | January 2008 |
| 5234 | Augmented BNF for Syntax Specifications: ABNFD. Crocker, Ed., P. Overell | Internet Standard | January 2008 |
| 5235 | Sieve Email Filtering: Spamtest and Virustest ExtensionsC. Daboo | Proposed Standard | January 2008 |
| 5236 | Improved Packet Reordering MetricsA. Jayasumana, N. Piratla, T. Banka, A. Bare, R. Whitner | Informational | June 2008 |
| 5237 | IANA Allocation Guidelines for the Protocol FieldJ. Arkko, S. Bradner | Best Current Practice | February 2008 |
| 5238 | Datagram Transport Layer Security (DTLS) over the Datagram Congestion Control Protocol (DCCP)T. Phelan | Proposed Standard | May 2008 |
| 5239 | A Framework for Centralized ConferencingM. Barnes, C. Boulton, O. Levin | Proposed Standard | June 2008 |
| 5240 | Protocol Independent Multicast (PIM) Bootstrap Router MIBB. Joshi, R. Bijlani | Proposed Standard | June 2008 |
| 5241 | Naming Rights in IETF ProtocolsA. Falk, S. Bradner | Informational | 1 April 2008 |
| 5242 | A Generalized Unified Character Code: Western European and CJK SectionsJ. Klensin, H. Alvestrand | Informational | 1 April 2008 |
| 5243 | OSPF Database Exchange Summary List OptimizationR. Ogier | Informational | May 2008 |
| 5244 | Definition of Events for Channel-Oriented Telephony SignallingH. Schulzrinne, T. Taylor | Proposed Standard | June 2008 |
| 5245 | Interactive Connectivity Establishment (ICE): A Protocol for Network Address Translator (NAT) Traversal for Offer/Answer ProtocolsJ. Rosenberg · obsoleted by RFC 8445, RFC 8839 | Proposed Standard | April 2010 |
| 5246 | The Transport Layer Security (TLS) Protocol Version 1.2T. Dierks, E. Rescorla · obsoleted by RFC 8446, RFC 9846 | Proposed Standard | August 2008 |
| 5247 | Extensible Authentication Protocol (EAP) Key Management FrameworkB. Aboba, D. Simon, P. Eronen | Proposed Standard | August 2008 |
| 5248 | A Registry for SMTP Enhanced Mail System Status CodesT. Hansen, J. Klensin | Best Current Practice | June 2008 |
| 5249 | Templates for Internet-Drafts Containing MIB ModulesD. Harrington, Ed. | Best Current Practice | July 2008 |
| 5250 | The OSPF Opaque LSA OptionL. Berger, I. Bryskin, A. Zinin, R. Coltun | Proposed Standard | July 2008 |
| 5251 | Layer 1 VPN Basic ModeD. Fedyk, Ed., Y. Rekhter, Ed., D. Papadimitriou, R. Rabbat, L. Berger | Proposed Standard | July 2008 |
| 5252 | OSPF-Based Layer 1 VPN Auto-DiscoveryI. Bryskin, L. Berger | Proposed Standard | July 2008 |
| 5253 | Applicability Statement for Layer 1 Virtual Private Network (L1VPN) Basic ModeT. Takeda, Ed. | Informational | July 2008 |
| 5254 | Requirements for Multi-Segment Pseudowire Emulation Edge-to-Edge (PWE3)N. Bitar, Ed., M. Bocci, Ed., L. Martini, Ed. | Informational | October 2008 |
| 5255 | Internet Message Access Protocol InternationalizationC. Newman, A. Gulbrandsen, A. Melnikov | Proposed Standard | June 2008 |
| 5256 | Internet Message Access Protocol - SORT and THREAD ExtensionsM. Crispin, K. Murchison | Proposed Standard | June 2008 |
| 5257 | Internet Message Access Protocol - ANNOTATE ExtensionC. Daboo, R. Gellens | Experimental | June 2008 |
| 5258 | Internet Message Access Protocol version 4 - LIST Command ExtensionsB. Leiba, A. Melnikov | Proposed Standard | June 2008 |
| 5259 | Internet Message Access Protocol - CONVERT ExtensionA. Melnikov, Ed., P. Coates, Ed. | Proposed Standard | July 2008 |
| 5260 | Sieve Email Filtering: Date and Index ExtensionsN. Freed | Proposed Standard | July 2008 |
| 5261 | An Extensible Markup Language (XML) Patch Operations Framework Utilizing XML Path Language (XPath) SelectorsJ. Urpalainen | Proposed Standard | September 2008 |
| 5262 | Presence Information Data Format (PIDF) Extension for Partial PresenceM. Lonnfors, E. Leppanen, H. Khartabil, J. Urpalainen | Proposed Standard | September 2008 |
| 5263 | Session Initiation Protocol (SIP) Extension for Partial Notification of Presence InformationM. Lonnfors, J. Costa-Requena, E. Leppanen, H. Khartabil | Proposed Standard | September 2008 |
| 5264 | Publication of Partial Presence InformationA. Niemi, M. Lonnfors, E. Leppanen | Proposed Standard | September 2008 |
| 5265 | Mobile IPv4 Traversal across IPsec-Based VPN GatewaysS. Vaarala, E. Klovning | Proposed Standard | June 2008 |
| 5266 | Secure Connectivity and Mobility Using Mobile IPv4 and IKEv2 Mobility and Multihoming (MOBIKE)V. Devarapalli, P. Eronen | Best Current Practice | June 2008 |
| 5267 | Contexts for IMAP4D. Cridland, C. King | Proposed Standard | July 2008 |
| 5268 | Mobile IPv6 Fast HandoversR. Koodli, Ed. · obsoleted by RFC 5568 | Proposed Standard | June 2008 |
| 5269 | Distributing a Symmetric Fast Mobile IPv6 (FMIPv6) Handover Key Using SEcure Neighbor Discovery (SEND)J. Kempf, R. Koodli | Proposed Standard | June 2008 |
| 5270 | Mobile IPv6 Fast Handovers over IEEE 802.16e NetworksH. Jang, J. Jee, Y. Han, S. Park, J. Cha | Informational | June 2008 |
| 5271 | Mobile IPv6 Fast Handovers for 3G CDMA NetworksH. Yokota, G. Dommety | Informational | June 2008 |
| 5272 | Certificate Management over CMS (CMC)J. Schaad, M. Myers · obsoleted by RFC 10002 | Proposed Standard | June 2008 |
| 5273 | Certificate Management over CMS (CMC): Transport ProtocolsJ. Schaad, M. Myers · obsoleted by RFC 10003 | Proposed Standard | June 2008 |
| 5274 | Certificate Management Messages over CMS (CMC): Compliance RequirementsJ. Schaad, M. Myers · obsoleted by RFC 10004 | Proposed Standard | June 2008 |
| 5275 | CMS Symmetric Key Management and DistributionS. Turner | Proposed Standard | June 2008 |
| 5276 | Using the Server-Based Certificate Validation Protocol (SCVP) to Convey Long-Term Evidence RecordsC. Wallace | Proposed Standard | August 2008 |
| 5277 | NETCONF Event NotificationsS. Chisholm, H. Trevino | Proposed Standard | July 2008 |
| 5278 | IANA Registration of Enumservices for Voice and Video MessagingJ. Livingood, D. Troshynski | Proposed Standard | July 2008 |
| 5279 | A Uniform Resource Name (URN) Namespace for the 3rd Generation Partnership Project (3GPP)A. Monrad, S. Loreto | Informational | July 2008 |
| 5280 | Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) ProfileD. Cooper, S. Santesson, S. Farrell, S. Boeyen, R. Housley, W. Polk | Proposed Standard | May 2008 |
| 5281 | Extensible Authentication Protocol Tunneled Transport Layer Security Authenticated Protocol Version 0 (EAP-TTLSv0)P. Funk, S. Blake-Wilson | Informational | August 2008 |
| 5282 | Using Authenticated Encryption Algorithms with the Encrypted Payload of the Internet Key Exchange version 2 (IKEv2) ProtocolD. Black, D. McGrew | Proposed Standard | August 2008 |
| 5283 | LDP Extension for Inter-Area Label Switched Paths (LSPs)B. Decraene, JL. Le Roux, I. Minei | Proposed Standard | July 2008 |
| 5284 | User-Defined Errors for RSVPG. Swallow, A. Farrel | Proposed Standard | August 2008 |
| 5285 | A General Mechanism for RTP Header ExtensionsD. Singer, H. Desineni · obsoleted by RFC 8285 | Proposed Standard | July 2008 |
| 5286 | Basic Specification for IP Fast Reroute: Loop-Free AlternatesA. Atlas, Ed., A. Zinin, Ed. | Proposed Standard | September 2008 |
| 5287 | Control Protocol Extensions for the Setup of Time-Division Multiplexing (TDM) Pseudowires in MPLS NetworksA. Vainshtein, Y(J). Stein | Proposed Standard | August 2008 |
| 5288 | AES Galois Counter Mode (GCM) Cipher Suites for TLSJ. Salowey, A. Choudhury, D. McGrew | Proposed Standard | August 2008 |
| 5289 | TLS Elliptic Curve Cipher Suites with SHA-256/384 and AES Galois Counter Mode (GCM)E. Rescorla | Proposed Standard | August 2008 |
| 5290 | Comments on the Usefulness of Simple Best-Effort TrafficS. Floyd, M. Allman | Informational | July 2008 |
| 5291 | Outbound Route Filtering Capability for BGP-4E. Chen, Y. Rekhter | Proposed Standard | August 2008 |
| 5292 | Address-Prefix-Based Outbound Route Filter for BGP-4E. Chen, S. Sangli | Proposed Standard | August 2008 |
| 5293 | Sieve Email Filtering: Editheader ExtensionJ. Degener, P. Guenther | Proposed Standard | August 2008 |
| 5294 | Host Threats to Protocol Independent Multicast (PIM)P. Savola, J. Lingard | Informational | August 2008 |
| 5295 | Specification for the Derivation of Root Keys from an Extended Master Session Key (EMSK)J. Salowey, L. Dondeti, V. Narayanan, M. Nakhjiri | Proposed Standard | August 2008 |
| 5296 | EAP Extensions for EAP Re-authentication Protocol (ERP)V. Narayanan, L. Dondeti · obsoleted by RFC 6696 | Proposed Standard | August 2008 |
| 5297 | Synthetic Initialization Vector (SIV) Authenticated Encryption Using the Advanced Encryption Standard (AES)D. Harkins | Informational | October 2008 |
| 5298 | Analysis of Inter-Domain Label Switched Path (LSP) RecoveryT. Takeda, Ed., A. Farrel, Ed., Y. Ikejiri, JP. Vasseur | Informational | August 2008 |