Development of l7-filter has moved to the Clear Foundation. These pages are out of date, but will remain as a historical record.

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L7-filter Supported Protocols

Below is the list of supported protocols. Note that most of the protocols are listed as needing more testing. We need your help (yes, you!) to do this. Simply reporting on how patterns are working for you is helpful. The easiest way to do this is to follow the wiki links by patterns you use. On the wiki, post your results in the l7-filter section of each page. You can also post to l7-filter-developers(@)lists(.)sf(.)net (you must subscribe first).

To help add support for more protocols, see the Pattern Writing HOWTO.

Key to symbols


The "quality" gives a rough idea of how well the pattern works. This is a conglomerate measure of several things, including (1) how well the protocol is understood (2) how much the pattern has been tested (3) in what variety of situations the pattern has been tested and (4) what fraction of identifiable traffic is identified correctly. For details, read the pattern file or the protocol's wiki entry.


The protocol package includes a tool for testing pattern performance. It tests them against 122 samples of actual network data (as of the 2009-05-19 release) 100,000 times each. The following times are for a 2 GHz Opteron.

The first speed shown for a pattern in the tables below is the speed when used in the kernel (with the old V8 regular expression library). The second is the speed when used in userspace (with the modern GNU library). Note that the userspace version has a smaller spread of speeds. That is, its slowest patterns are faster and its fastest patterns are slower than the kernel version.

Other notes


Protocols are marked as being in one or more "groups". Some groups refer to what sort of purpose each protocol has. These allow front-ends to treat a set of protocols in the same way without requiring the user to select (or know about) each individual protocol. For instance, an application could have a checkbox for "VoIP" rather than one for Skype, one for H.323, etc..

Other groups indicate whether a protocol is documented in an IETF RFC, whether it is standardized by any official body, a non-standard but used primarily by open source programs, or proprietary. Among other things, this is supposed to give some idea of how volatile these protocols are likely to be. IETF standards are highly unlikely to change behavior and break l7-filter's patterns suddenly. (Although if programs misimplement them, anything can happen.) Open source non-standardized protocols are somewhat more likely to change abruptly, but changes are likely to be publically documented and, of course, the source code can be read to learn about them as a last resort. Proprietary protocols can change at any time without warning. The nature of the changes may be a closely kept secret.

Not all groups that exist in the pattern files have icons shown on this page. Also, just because a protocol is not listed as being in a group does not mean that it is specifically excluded from that group. For instance, not every protocol without "secure" is insecure. We invite you to make the groups more complete by sending corrections/additions to our mailing list.


The pattern name is what you must use when issuing l7-filter commands. The names below link to the pattern files. Select column headings to sort.

bad third line in replaytv-ivs.pat
wiki100bao[very fast] [fast] ok [P2P]100bao - a Chinese P2P protocol/program -
wikiapplejuice[very fast] [fast] great [P2P]Apple Juice - P2P filesharing -
wikiares[very fast] [fast] good [P2P][Open source]undermatch Ares - P2P filesharing -
wikibattlefield1942[very fast] [fast] ok [Game][Proprietary]Battlefield 1942 - An EA game
wikibgp[very fast] [fast] ok [Networking][IETF draft standard]BGP - Border Gateway Protocol - RFC 1771
wikiciscovpn[very fast] [fast] ok [Remote access][Proprietary]Cisco VPN - VPN client software to a Cisco VPN server
wikicounterstrike-source[very fast] [fast] good [Game][Proprietary]Counterstrike (using the new "Source" engine) - network game
wikicvs[very fast] [fast] good [Version control][Open source]CVS - Concurrent Versions System
wikidayofdefeat-source[very fast] [fast] good [Game][Proprietary]Day of Defeat: Source - game (Half-Life 2 mod) -
wikidhcp[very fast] [fast] good [Networking][IETF draft standard]DHCP - Dynamic Host Configuration Protocol - RFC 1541
wikidoom3[very fast] [fast] good [Game][Proprietary]Doom 3 - computer game
wikifreenet[very fast] [fast] poor [P2P][Document retrieval][Open source]Freenet - Anonymous information retrieval -
wikigkrellm[very fast] [fast] great [Monitoring][Open source]Gkrellm - a system monitor -
wikiguildwars[very fast] [fast] marginal [Game][Proprietary]Guild Wars - online game -
wikih323[very fast] [fast] ok [VoIP][Other standard]H.323 - Voice over IP.
wikihalflife2-deathmatch[very fast] [fast] good [Game][Proprietary]Half-Life 2 Deathmatch - popular computer game
wikihddtemp[very fast] [fast] great [Monitoring][Open source]hddtemp - Hard drive temperature reporting
wikimohaa[very fast] [fast] good [Game][Proprietary]Medal of Honor Allied Assault - an Electronic Arts game
wikipcanywhere[very fast] [fast] marginal [Remote access][Proprietary]pcAnywhere - Symantec remote access program
wikipoco[very fast] [fast] ok [P2P]POCO and PP365 - Chinese P2P filesharing -
wikiwikiwikiquake-halflife[very fast] [fast] good [Game][Proprietary]Half Life 1 engine games (HL 1, Quake 2/3/World, Counterstrike 1.6, etc.)
wikiquake1[very fast] [fast] marginal [Game][Proprietary]Quake 1 - A popular computer game.
wikiradmin[very fast] [fast] ok [Remote access][Proprietary]Famatech Remote Administrator - remote desktop for MS Windows
wikirunesofmagic[very fast] [fast] ok [Game][Proprietary]Runes of Magic - game -
wikiskypetoskype[very fast] [fast] ok [VoIP][P2P][Proprietary]overmatch Skype to Skype - UDP voice call (program to program) -
wikisnmp[very fast] [fast] good [Networking][IETF standard]superset SNMP - Simple Network Management Protocol - RFC 1157
wikissh[very fast] [fast] great [Remote access][Secure][IETF draft standard]SSH - Secure SHell
wikistun[very fast] [fast] ok [Networking][IETF proposed standard]STUN - Simple Traversal of UDP Through NAT - RFC 3489
wikisubspace[very fast] [fast] marginal [Game]Subspace - 2D asteroids-style space game -
wikisubversion[very fast] [fast] ok [Version control][Open source]Subversion - a version control system
wikiteamfortress2[very fast] [fast] good [Game][Proprietary]Team Fortress 2 - network game -
wikiteamspeak[very fast] [fast] good [VoIP][Proprietary]TeamSpeak - VoIP application -
wikitelnet[very fast] [fast] good [Remote access][Obsolete][IETF standard]Telnet - Insecure remote login - RFC 854
wikithecircle[very fast] [fast] ok [P2P][Open source]The Circle - P2P application -
wikitsp[very fast] [fast] good [Time synchronization][Open source]overmatch TSP - Berkely UNIX Time Synchronization Protocol
wikiuucp[very fast] [fast] ok [Document retrieval][Obsolete]UUCP - Unix to Unix Copy
wikivnc[very fast] [fast] great [Remote access]VNC - Virtual Network Computing. Also known as RFB - Remote Frame Buffer
wikiworldofwarcraft[very fast] [fast] ok [Game][Proprietary]World of Warcraft - popular network game -
wikizmaap[very fast] [fast] ok [Networking][IETF draft standard]ZMAAP - Zeroconf Multicast Address Allocation Protocol
wikibattlefield2142[fast] [fast] ok [Proprietary][Game]Battlefield 2142 - An EA game.
wikibiff[fast] [fast] good [Mail]undermatch overmatch Biff - new mail notification
wikichikka[fast] [fast] good [Proprietary][Chat]superset Chikka - SMS service which can be used without phones -
wikidazhihui[fast] [fast] ok Dazhihui - stock analysis and trading; Chinese -
wikidirectconnect[fast] [fast] good [P2P]Direct Connect - P2P filesharing -
wikiedonkey[fast] [fast] good [P2P]overmatch eDonkey2000 - P2P filesharing - and others
wikihotline[fast] [fast] marginal [P2P]Hotline - An old P2P filesharing protocol
wikiident[fast] [fast] good [Networking][IETF proposed standard]Ident - Identification Protocol - RFC 1413
wikiimap[fast] [fast] great [Mail][IETF proposed standard]IMAP - Internet Message Access Protocol (A common e-mail protocol)
wikiirc[fast] [fast] great [Chat][IETF proposed standard]IRC - Internet Relay Chat - RFC 1459
wikikugoo[fast] [fast] ok [P2P]KuGoo - a Chinese P2P program -
wikiliveforspeed[fast] [fast] poor [Game][Proprietary]Live For Speed - A racing game.
wikilpd[fast] [fast] ok [Printer][ Non-standards track RFC'd]LPD - Line Printer Daemon Protocol (old-style UNIX printing) - RFC 1179
wikimsn-filetransfer[fast] [fast] good [Chat][Document retrieval][Proprietary]MSN (Micosoft Network) Messenger file transfers (MSNFTP and MSNSLP)
wikimute[fast] [fast] marginal [P2P][Open source]MUTE - P2P filesharing -
wikinapster[fast] [fast] good [P2P]Napster - P2P filesharing
wikincp[fast] [fast] good [Networking][Proprietary]NCP - Novell Core Protocol
wikinntp[fast] [fast] good [IETF proposed standard]NNTP - Network News Transfer Protocol - RFCs 977 and 2980
wikintp[fast] [fast] good [Time synchronization][IETF draft standard]overmatch (S)NTP - (Simple) Network Time Protocol - RFCs 1305 and 2030
wikipop3[fast] [fast] great [Mail][IETF standard]POP3 - Post Office Protocol version 3 (popular e-mail protocol) - RFC 1939
wikireplaytv-ivs[fast] [fast] good ReplayTV Internet Video Sharing - Digital Video Recorder -
wikirlogin[fast] [fast] ok [Remote access][ Non-standards track RFC'd]rlogin - remote login - RFC 1282
wikirtp[fast] [fast] ok [Streaming video][IETF standard]undermatch overmatch RTP - Real-time Transport Protocol - RFC 3550
wikisip[fast] [fast] good [VoIP][IETF proposed standard]SIP - Session Initiation Protocol - Internet telephony - RFC 3261, 3265, etc.
wikisoulseek[fast] [fast] good [P2P]Soulseek - P2P filesharing -
wikitftp[fast] [fast] marginal [Document retrieval][IETF standard]TFTP - Trivial File Transfer Protocol - used for bootstrapping - RFC 1350
wikitonghuashun[fast] [fast] ok Tonghuashun - stock analysis and trading; Chinese -
wikiventrilo[fast] [fast] good [VoIP][Proprietary]Ventrilo - VoIP -
wikiyahoo[fast] [fast] good [Chat][Proprietary]Yahoo messenger - an instant messenger protocol -
wikix11[not so fast] [very fast] good [Remote access][Other standard]X Windows Version 11 - Networked GUI system used in most Unices
wikiimesh[fast] [not so fast] ok [P2P]iMesh - the native protocol of iMesh, a P2P application -
wikismb[fast] [not so fast] good [Document retrieval][Networking][Proprietary]Samba/SMB - Server Message Block - Microsoft Windows filesharing
wikiftp[not so fast] [fast] great [Document retrieval][IETF standard]FTP - File Transfer Protocol - RFC 959
wikihttp-rtsp[not so fast] [fast] ok [Streaming audio][Streaming video][IETF draft standard]subset RTSP tunneled within HTTP
wikiqq[not so fast] [fast] good [Chat]Tencent QQ Protocol - Chinese instant messenger protocol -
wikismtp[not so fast] [fast] great [Mail][IETF standard]SMTP - Simple Mail Transfer Protocol - RFC 2821 (See also RFC 1869)
wikissl[not so fast] [fast] good [Secure][IETF proposed standard]superset SSL and TLS - Secure Socket Layer / Transport Layer Security - RFC 2246
wikiaimwebcontent[not so fast] [not so fast] good [Chat][Document retrieval][Proprietary]AIM web content - ads/news content downloaded by AOL Instant Messenger
wikicimd[not so fast] [not so fast] good [Proprietary][Chat]subset Computer Interface to Message Distribution, an SMSC protocol by Nokia
wikicitrix[not so fast] [not so fast] marginal [Remote access][Proprietary]Citrix ICA - proprietary remote desktop application -
wikignucleuslan[not so fast] [not so fast] good [P2P][Open source]GnucleusLAN - LAN-only P2P filesharing
wikignutella[not so fast] [not so fast] good [P2P][Open source]Gnutella - P2P filesharing
wikiipp[not so fast] [not so fast] good [Printer][IETF proposed standard]IP printing - a new standard for UNIX printing - RFC 2911
wikijabber[not so fast] [not so fast] good [Chat][IETF proposed standard]Jabber (XMPP) - open instant messenger protocol - RFC 3920 -
wikilive365[not so fast] [not so fast] marginal [Streaming audio]live365 - An Internet radio site -
wikinetbios[not so fast] [not so fast] marginal [Networking][IETF standard][Proprietary]NetBIOS - Network Basic Input Output System
wikiopenft[not so fast] [not so fast] good [P2P][Open source]OpenFT - P2P filesharing (implemented in giFT library)
wikipplive[not so fast] [not so fast] ok [P2P][Streaming video][Proprietary]PPLive - Chinese P2P streaming video -
wikirdp[not so fast] [not so fast] ok [Remote access][Proprietary]RDP - Remote Desktop Protocol (used in Windows Terminal Services)
wikirtsp[not so fast] [not so fast] good [Streaming video][IETF proposed standard]RTSP - Real Time Streaming Protocol - - RFC 2326
wikisocks[not so fast] [not so fast] good [Networking][IETF proposed standard]SOCKS Version 5 - Firewall traversal protocol - RFC 1928
wikitor[not so fast] [not so fast] good [Networking]Tor - The Onion Router - used for anonymization -
wikiwhois[not so fast] [not so fast] good [Networking][IETF draft standard]overmatch Whois - query/response system, usually used for domain name info - RFC 3912
wikidns[slow] [fast] great [Networking][IETF standard]DNS - Domain Name System - RFC 1035
wikiaim[slow] [not so fast] good [Chat][Proprietary]AIM - AOL instant messenger (OSCAR and TOC)
wikiarmagetron[slow] [not so fast] good [Open source][Game]Armagetron Advanced - open source Tron/snake based multiplayer game
wikibattlefield2[slow] [not so fast] ok [Game][Proprietary]Battlefield 2 - An EA game.
wikibittorrent[slow] [not so fast] good [P2P][Open source]undermatch Bittorrent - P2P filesharing / publishing tool -
wikifasttrack[slow] [not so fast] good [P2P]FastTrack - P2P filesharing (Kazaa, Morpheus, iMesh, Grokster, etc)
wikigoboogy[slow] [not so fast] marginal [P2P]GoBoogy - a Korean P2P protocol
wikigopher[slow] [not so fast] good [Document retrieval][Obsolete][ Non-standards track RFC'd]undermatch Gopher - A precursor to HTTP - RFC 1436
wikihttp[slow] [not so fast] great [Document retrieval][IETF draft standard]superset HTTP - HyperText Transfer Protocol - RFC 2616
wikimsnmessenger[slow] [not so fast] good [Chat][Proprietary]MSN Messenger - Microsoft Network chat client
wikinbns[slow] [not so fast] good [Networking][Proprietary]NBNS - NetBIOS name service
wikishoutcast[slow] [not so fast] good [Streaming audio]Shoutcast and Icecast - streaming audio
wikiskypeout[slow] [not so fast] ok [VoIP][P2P][Proprietary]overmatch Skype to phone - UDP voice call (program to POTS phone) -
wikisoribada[slow] [not so fast] good [P2P]Soribada - A Korean P2P filesharing program/protocol -
wikissdp[slow] [not so fast] good [Networking][IETF draft standard]SSDP - Simple Service Discovery Protocol - easy discovery of network devices
wikitesla[slow] [not so fast] marginal [P2P]Tesla Advanced Communication - P2P filesharing (?)
wikivalidcertssl[slow] [not so fast] good [Secure][IETF proposed standard]subset Valid certificate SSL
wikixboxlive[slow] [not so fast] marginal [Game][Proprietary]XBox Live - Console gaming
wikixunlei[slow] [not so fast] good [P2P]Xunlei - Chinese P2P filesharing -
wikifinger[slow] [slow] good [IETF draft standard]undermatch overmatch Finger - User information server - RFC 1288


These patterns were judged to be of lesser general interest than those above.

wikigtalk[very fast] [fast] good [Chat][IETF proposed standard]subset GTalk, a Jabber (XMPP) client
wikisnmp-mon[very fast] [fast] good [Networking][IETF standard]subset SNMP Monitoring - Simple Network Management Protocol (RFC1157)
wikisnmp-trap[very fast] [fast] good [Networking][IETF standard]subset SNMP Traps - Simple Network Management Protocol (RFC1157)
wikiaudiogalaxy[fast] [fast] ok [P2P][Obsolete]Audiogalaxy - (defunct) Peer to Peer filesharing
wikihttp-dap[not so fast] [not so fast] good [Document retrieval][IETF draft standard]subset HTTP by Download Accelerator Plus -
wikihttp-freshdownload[not so fast] [not so fast] good [Document retrieval][IETF draft standard]subset HTTP by Fresh Download -
wikihttp-itunes[not so fast] [not so fast] good [Streaming audio][IETF draft standard]subset HTTP - iTunes (Apple's music program)
wikihttpaudio[not so fast] [not so fast] good [Streaming audio][Document retrieval][IETF draft standard]subset HTTP - Audio over HyperText Transfer Protocol (RFC 2616)
wikihttpcachehit[not so fast] [not so fast] good [Document retrieval][IETF draft standard]subset HTTP - Proxy Cache hit for HyperText Transfer Protocol (RFC 2616)
wikihttpcachemiss[not so fast] [not so fast] good [Document retrieval][IETF draft standard]subset HTTP - Proxy Cache miss for HyperText Transfer Protocol (RFC 2616)
wikihttpvideo[not so fast] [not so fast] good [Streaming video][Document retrieval][IETF draft standard]subset HTTP - Video over HyperText Transfer Protocol (RFC 2616)
wikipressplay[not so fast] [not so fast] ok [Document retrieval][Obsolete][Proprietary]pressplay - A legal music distribution site -
wikiquicktime[not so fast] [not so fast] good [Streaming video][Streaming audio][IETF draft standard]subset Quicktime HTTP

File Types

This category of patterns is for file types. This sort of matching is not the focus of l7-filter, but it can be done in some cases. It requires some extra set up, so read the File Types README.

html[fast] [not so fast] good [File]subset (X)HTML - (Extensible) Hypertext Markup Language -
jpeg[fast] [not so fast] ok [File]subset JPEG - Joint Picture Expert Group image format.
pdf[fast] [not so fast] good [File]subset PDF - Portable Document Format - Postscript-like format by Adobe
perl[fast] [not so fast] good [File]subset Perl - A scripting language by Larry Wall.
png[fast] [not so fast] good [File]subset PNG - Portable Network Graphics, a popular image format
postscript[fast] [not so fast] good [File]subset Postscript - Printing Language
rpm[fast] [not so fast] good [File]subset RPM - Redhat Package Management packages
rtf[fast] [not so fast] good [File]subset RTF - Rich Text Format - an open document format
exe[not so fast] [not so fast] good [File]subset Executable - Microsoft PE file format.
gif[not so fast] [not so fast] good [File]subset GIF - Popular Image format.
mp3[not so fast] [not so fast] good [File]subset MP3 - Moving Picture Experts Group Audio Layer III
ogg[not so fast] [not so fast] ok [File]subset Ogg - Ogg Vorbis music format (not any ogg file, just vorbis)
rar[not so fast] [not so fast] good [File]subset RAR - The WinRAR archive format
tar[not so fast] [not so fast] good [File]subset Tar - tape archive. Standard UNIX file archiver, not just for tapes.
zip[not so fast] [not so fast] good [File]subset ZIP - (PK|Win)Zip archive format
flash[slow] [not so fast] good [File]subset Flash - Macromedia Flash.


This category is for worms, viruses, and anything else that uses the network to bother us. It doesn't appear that there is much demand for this functionality, but in case it interests you, this is a proof-of-concept. Malware README.

wikicode_red[fast] [not so fast] ok subset Code Red - a worm that attacks Microsoft IIS web servers
wikinimda[not so fast] [not so fast] ok subset Nimda - a worm that attacks Microsoft IIS web servers, and MORE!


Computer code associated with l7-filter, such as these the protocol definitions, is licensed under the GNU GPLv2.