Saturday, 19 July 2014

Simple and Basic Understanding of HTTP

INTRODUCTION: 


HTTP stands for  Hyper text transfer protocol .Before i will go into Http , let me explain what is protocol? In computer world protocol it is more or less like the manners or rule how computer layers or components interact with each other.When visiting Web sites, the client application makes connections to Web servers via a network protocol called HTTP. These network connections support sending response data from servers back to clients including the content of Web pages and also some protocol control information. 

EXPLANATION  

There is big/complex model made of 7 layers known as OSI Model as shown below



HTTP is just a small piece this model. So, lets what each word denotes in HTTP  acronym. The T and the P together are the transfer protocol and HT, or hypertext, is the something that gets transferred with this protocol. Being more specific about hypertext, it is just when you create webpage and put come links for connecting/jump from one page to another. So, this hypertext needs to fallow some convention or rules.On the other side of the network we essentially have nothing more than your computer but instead of a browser with another piece of software, a web server. Of course, that computer also has HTTP installed. Here the protocol is linked with this web server software which will get the request and according to it will answer with a response. This response, again according to the rules set in the protocol, will be send back to your computer where the browser will understand what is going on and present the response to you. 

 HTTP (Hypertext Transfer Protocol) is the most popular application protocol used in the Internet

HTTP is an asymmetric request-response client-server protocol .  An HTTP client sends a request message to an HTTP server.  The server, in turn, returns a response message.  

HTTP is a stateless protocol means the current request does not know what has been done in the previous requests.
 



Whenever you issue a URL from your browser to get a web resource using HTTP, e.g. http://www.shabirhakim.net/index.html, the browser turns the URL into a request message and sends it to the HTTP server. The HTTP server interprets the request message, and returns back you an appropriate response message, which is either the resource you requested or an error message. This process is illustrated below:



Uniform Resource Locator (URL)

A URL (Uniform Resource Locator) is used to uniquely identify a resource over the web. URL has the following syntax:

protocol://hostname:port/path-and-file-name
There are 4 parts in a URL:

  1. Protocol: The application-level protocol used by the client and server, e.g., HTTP, FTP, and telnet.
  2. Hostname: The DNS domain name (e.g., www.shabirhakim.net) or IP address (e.g., 192.128.1.2) of the server.
  3. Port: The TCP port number that the server is listening for incoming requests from the clients.
  4. Path-and-file-name: The name and location of the requested resource, under the server document base directory.
NOTE:HTTP is a client-server application-level protocol. It typically runs over a TCP/IP connection, as illustrated above. 

HTTP Request Methods

HTTP protocol defines a set of request methods. A client can use one of these request methods to send a request message to an HTTP server. The methods are:

GET: A client can use the GET request to get a web resource from the server.
HEAD: A client can use the HEAD request to get the header that a GET request would have obtained. Since the header contains the last-modified date of the data, this can be used to check against the local cache copy.
POST: Used to post data up to the web server.
PUT: Ask the server to store the data.
DELETE: Ask the server to delete the data.
TRACE: Ask the server to return a diagnostic trace of the actions it takes.
OPTIONS: Ask the server to return the list of request methods it supports.
CONNECT: Used to tell a proxy to make a connection to another host and simply reply the content, without attempting to parse or cache it. This is often used to make SSL connection through the proxy.


Response Status Code

The first line of the response message (status line) contains the response status code, which is generated by the server to indicate the result of the request.

The status code is a 3-digit number:

 1xx (Informational): Request received, server is continuing the process.
  2xx (Success): The request was successfully received, understood, accepted and serviced.
  3xx (Redirection): Further action must be taken in order to complete the request.
  4xx (Client Error): The request contains bad syntax or cannot be understood.
  5xx (Server Error): The server failed to fulfill an apparently valid request.


COMMONLY ENCOUNTERED STATUS CODE:
100 Continue: The server received the request and in the process of giving the response.
200 OK: The request is fulfilled.
301 Move Permanently: The resource requested for has been permanently moved to a new location. The URL of the new location is given in the response header called Location. The client should issue a new request to the new location. Application should update all references to this new location.
302 Found & Redirect (or Move Temporarily): Same as 301, but the new location is temporarily in nature. The client should issue a new request, but applications need not update the references.
304 Not Modified: In response to the If-Modified-Since conditional GET request, the server notifies that the resource requested has not been modified.
400 Bad Request: Server could not interpret or understand the request, probably syntax error in the request message.
401 Authentication Required: The requested resource is protected, and require client’s credential (username/password). The client should re-submit the request with his credential (username/password).
403 Forbidden: Server refuses to supply the resource, regardless of identity of client.
404 Not Found: The requested resource cannot be found in the server.
405 Method Not Allowed: The request method used, e.g., POST, PUT, DELETE, is a valid method. However, the server does not allow that method for the resource requested.
408 Request Timeout:
414 Request URI too Large:
500 Internal Server Error: Server is confused, often caused by an error in the server-side program responding to the request.
501 Method Not Implemented: The request method used is invalid (could be caused by a typing error, e.g., "GET" misspell as "Get").
502 Bad Gateway: Proxy or Gateway indicates that it receives a bad response from the upstream server.
503 Service Unavailable: Server cannot response due to overloading or maintenance. The client can try again later.
504 Gateway Timeout: Proxy or Gateway indicates that it receives a timeout from an upstream server.

Finally , 
CONCLUSION : 
HTTP is an application-level protocol for distributed, collaborative, hypermedia information systems. It is a generic, stateless, protocol which can be used for many tasks beyond its use for hypertext, such as name servers and distributed object management systems, through extension of its request methods, error codes and headers. A feature of HTTP is the typing and negotiation of data representation, allowing systems to be built independently of the data being transferred

PROTOCOLS WITH RESPECTIVE FAMILIES


Protocol Family
(ISO8073)
A1
A10
A11
A12
A13
A14
A15
A3
A7
A8
A9
AAL2(Offline)
AARP
Abis
Abis
ACSE
ADSP
AEP
AFP
AH
AH
AMR
AppleArp
AppleTalk
ARP/RARP
ASP
ATCP
ATMCell(AAL0-AAL5)
ATMCellNNI
ATMCellUNI
ATMCircuitEmulation
ATMP
ATMSAR
ATP
AVAYA(Skinny)
BACP
Banyan
BAP
BCAST
BCC
BCC
BCP
BGMP
BGP-4
BICC
B-ICI
B-ISUP
BMC
BMP
BPDU
BSD
BSMAP
BSSAP
BSSAP+
BSSAP+
BSSGP
BSSMAP
BTSM
BTSM/LAPD
BVCP
CAMEL
CAMEL
Cascade
CC
CC
CC
CCP
CDP
CHAP
CIF
CiscoISL
CiscoRouter
CiscoSRB
CMIP
COPS
CTERM
DAP
DCAP
DDP
DEC_LANBridge
DEC_LAT
DEC_LAVC
DEC_MOP_D/L
DEC_MOP_RC
DEC_Route
DESE
DHCP
DHCPv6
DIAG
DIS
DISL
DLSw
DNCP
DNS
DriP
DSMCC
DTAP
DUP
DVB
DVMRP
EAP
ECP
EGP
EIGRP
ELCP
ES-IS
ESP
ESP
Ethernet
EtherTalk
FANP
FDDI
Finger
FP
FrameRelay
FrameRelayOverATM
FrameRelayOverLAPF
FrameRelayOverLLC
FrameRelayOverSNA
FRF.9(DCP)
FRF10
FRF11
FRF12
FRF16
FRF4
FRF5
FRF8
FTAM
FTP
FUNI
G711
G723.1
G729
GARP
GCC
GCC
GCP
GMM/SM
GMM/SM
GMRP
GOPHER
GR-303(IDLC/LAPD)
GRE
GSMP
GTP
GTP
GTP'
GVRP
H.225
H.235
H.245
H.261
H.263
H.450.1
H.450.10
H.450.11
H.450.12
H.450.2
H.450.3
H.450.4
H.450.5
H.450.6
H.450.7
H.450.8
H.450.9
H225G
H225G
HDLC
HPR-APPN
HSRP
HTTP
ICMP
ICMPv6
ICP
ICPv2
IDLC
IDP
IDRP
IDRP
IFMP
IGMP
IGRP
IISP
ILMI
IMAP4
IMPP
INAP
IP
IPARSEoverX.25overLAPB
IPC
IPCP
IPDC
IPOverATM
IPOverHDLC
IPv6
IPv6CP
IPX
IPXCP
IRC
ISAKMP/IKE
ISDN
IS-IS
ISL
ISO-IP(CLNP)
ISOoverX.25
ISO-PP
ISO-SP
ISO-TP
ISUP
ITUQ2931
ITUQ2971
IuUP
L2F
L2TP
LAPB
LAPD
LAPF
LAPV5
LAPV5DL
LAT
LAVC
LCP
LDAP
LDP
LE802.3
LE802.5
LEControl
LES(PSTN)
LEX
LEXCP
LLC
LLC
LQR
LZS
M2PA
M2UA
M3UA
MAC
MAP
MAP
MAPOS
MARS
MDLP
MDTP
Megaco(ASCII+ASN.1)
Megaco(H.248)
MegacooverATM
MGCP
MLP
MM
MM
MM
MMS
MNRP
MNTv1
MobileIP
MOP
MOUNT
MPEG-2
MPLS
MPLSoverATM
MPPC
MTP-2
MTP-3
MTP3B
MultiPPP
MZAP
NARP
NBAP
NBFCP
NBP
NCP
NDS
NetBIOS
NetBIOS/IP
NetRPC
NFS
NHDR
NHRP
NHRP
NLM
NLP
NLSP
NNIPVC
NNISVC
NovelNetBIOS
NS
NSM
NSP
NSP
NTP
O&M
OSINLCP
OSPF
PAP
PAP
PDCP
PEP
PIM
PMAP
PNNIRouting
PNNISignaling
POP3
PPP
PPP-BPDU
PPPMultilink
PPPoE
PPPoverATM
PPPoverHDLC
PPPoverLAPB
PPPoverLAPF
PPTP
Proteon
PROXY(Skinny)
Q.2140
Q.2140
Q.SAAL
Q2630
QLLC
Radius
RANAP
RAS
Rexec
RIP
RIP2
RIPngforIPv6
RIPX
RLC
RLC/MAC
Rlogin
RLP
RLP
RND
RNSAP
ROSE
RP
RPC
RPCB
RPCB
Rprint
RR
RR
RR
RRC
Rshell
RSVP
RTCP
RTMP
RTP
RTP
RTSP
RUDP
RVPoverIP
Rwho
SAMOverFREther
SAMOverX.25OverLAPB
SAP
SAPv2
SCCP
SCP
SCSP
SCTP
SCTP
SDCP
SDCP
SDLC
SDP
SER
SGCP
SIP
SIP-L3
Skinny
SLP
SMB
SMPP
SMS
SMS
SMS
SMS(TP)
SMS(TP)
SMSCB
SMS-CB
SMSCB
SMT
SMTP
SNA
SNA5250
SNACP
SNAoverSDLC
SNAP
SNARH
SNATerminology
SNATH
SNATHO-THS
SNDCP
SNDCP
SNDCP
SNMP
SOCKS
SPANS
SPANS
SPP
SPP
SPX
SRP
SS
SS
SS
SSP
STP
StreetTalk
T.125
T.38
TACACS+
TALI
TCAP
TCP
TDP
TELNET
TFTP
THDR
Timeplex(BRE2)
TokenRing
TOM
TPKT
TRAU
TRIP
TUP
UDP
UNI3.x
UNI4.0
UNISVC
V5
V5-BCC
V5-Control
V5-LinkControl
V5-Protection
V5-PSTN
VanJacobson
VARP
VB51
VIP
VIVIDarm
VIVIDbme
VIVIDccp
ViVIDMPOA
VLAN(802.1Q)
VRRP
VTP
WCCP
WCMP
WDOG
WDP
Wellfleet
WSP
WTLS
WTP
X.25
X.75
XOT
X-Window
YP(NIS)
ZIP
ISO
CDMA2000
CDMA2000
CDMA2000
CDMA2000
CDMA2000
CDMA2000
CDMA2000
CDMA2000
CDMA2000
CDMA2000
CDMA2000
ATM
AppleTalk
Cellular
GPRS
ISO
AppleTalk
AppleTalk
AppleTalk
IPSecurity
TCP/IP
UMTS
AppleTalk
AppleTalk
TCP/IP
AppleTalk
PPP
ATM
ATM
ATM
Audio/VisualOver ATM
TCP/IP
ATM
AppleTalk
VoIP
PPP
Banyan
PPP
Novell
GPRS
UMTS
PPP
TCP/IP
TCP/IP
SS7
ATMSignaling&Routing
ATMSignaling&Routing
UMTS
Novell
Bridge/Router
PPP
Cellular
Cellular
GPRS
UMTS
GPRS
Cellular
Cellular
Cellular
PPP
GPRS
UMTS
FrameRelay
Cellular
GPRS
UMTS
PPP
Bridge/Router
PPP
LANDataLinkLayer
Bridge/Router
Bridge/Router
Bridge/Router
ISO
TCP/IP
DECnet
DECnet
TCP/IP
AppleTalk
DECnet
DECnet
DECnet
DECnet
DECnet
DECnet
PPP
TCP/IP
TCP/IP
Novell
LANDataLinkLayer
Bridge/Router
IBM
PPP
TCP/IP
Bridge/Router
Audio/VisualOverATM
Cellular
SS7
Audio/VisualOverATM
TCP/IP
PPP
PPP
TCP/IP
TCP/IP
VoDSL
ISO
IPSecurity
TCP/IP
LANDataLinkLayer
AppleTalk
TCP/IP
LANDataLinkLayer
TCP/IP
UMTS
FrameRelay
FrameRelay
FrameRelay
FrameRelay
FrameRelay
FrameRelay
FrameRelay
FrameRelay
FrameRelay
FrameRelay
FrameRelay
FrameRelay
FrameRelay
ISO
TCP/IP
FUNI
VoIP
VoIP
VoIP
LANDataLinkLayer
GPRS
UMTS
UMTS
GPRS
UMTS
LANDataLinkLayer
TCP/IP
GR-303
TCP/IP
IPSwitching
GPRS
UMTS
UMTS
LANDataLinkLayer
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
H.323
X.25
IBM
TCP/IP
TCP/IP
TCP/IP
TCP/IP
TCP/IP
TCP/IP
GR-303
XNS
ISO
TCP/IP
IPSwitching
TCP/IP
TCP/IP
ATMSignaling&Routing
ILMI
TCP/IP
TCP/IP
SS7
TCP/IP
X.25
Banyan
PPP
TCP/IP
ATM
X.25
TCP/IP
PPP
Novell
PPP
TCP/IP
IPSecurity
ISDN
ISO
TagSwitchingr
ISO
ISO
ISO
ISO
ISO
SS7
ATMSignaling&Routing
ATMSignaling&Routing
UMTS
TCP/IP
TCP/IP
X.25
ISDN
FrameRelay
V5.1/V5.2
VoDSL
DECnet
DECnet
PPP
TCP/IP
TCP/IP
LANEmulation
LANEmulation
LANEmulation
VoDSL
PPP
PPP
GPRS
LANDataLinkLayer
PPP
PPP
Sigtran
Sigtran
Sigtran
UMTS
GPRS
UMTS
Bridge/Router
TCP/IP
CDPD
TCP/IP
TCP/IP
VoIP
VoIP
VoIP
X.25
Cellular
GPRS
UMTS
Cellular
CDPD
SUN
TCP/IP
DECnet
SUN
Audio/VisualOverATM
TagSwitchingr
TagSwitchingr
PPP
SS7
SS7
UMTS
PPP
TCP/IP
TCP/IP
UMTS
PPP
AppleTalk
Novell
Novell
IBM
TCP/IP
Banyan
SUN
IBM
IBM
TCP/IP
SUN
IBM
Novell
FrameRelay
FrameRelay
Novell
GPRS
SUN
Bridge/Router
DECnet
TCP/IP
Cellular
PPP
TCP/IP
AppleTalk
PPP
UMTS
XNS
TCP/IP
SUN
ATMSignaling&Routing
ATMSignaling&Routing
TCP/IP
PPP
PPP
PPP
PPP
PPP
PPP
PPP
PPP
TCP/IP
Bridge/Router
VoIP
ATMSignaling&Routing
SS7
ATMSignaling&Routing
UMTS
IBM
TCP/IP
UMTS
H.323
UNIX
XNS
TCP/IP
TCP/IP
Novell
UMTS
GPRS
UNIX
Cellular
UMTS
Bridge/Router
UMTS
ISO
DECnet
SUN
SUN
SUN
UNIX
Cellular
GPRS
UMTS
UMTS
UNIX
TCP/IP
H.323
AppleTalk
Banyan
H.323
TCP/IP
TCP/IP
VoIP
UNIX
FrameRelay
X.25
Novell
VoIP
SS7
DECnet
TCP/IP
Sigtran
TCP/IP
PPP
TCP/IP
IBM
VoIP
Novell
VoIP
VoIP
SMDS
VoIP
TCP/IP
IBM
TCP/IP
Cellular
GPRS
UMTS
GPRS
UMTS
Cellular
GPRS
UMTS
LANDataLinkLayer
TCP/IP
IBM
IBM
PPP
IBM
LANDataLinkLayer
IBM
IBM
IBM
IBM
CDPD
GPRS
UMTS
TCP/IP
TCP/IP
ATMSignaling&Routing
ATMSignaling&Routing
Banyan
XNS
Novell
LANDataLinkLayer
Cellular
GPRS
UMTS
Bridge/Router
DECnet
Banyan
H.323
H.323
TCP/IP
Sigtran
SS7
TCP/IP
TagSwitchingr
TCP/IP
TCP/IP
IBM
FrameRelay
LANDataLinkLayer
GPRS
H.323
Cellular
TCP/IP
SS7
TCP/IP
ATMSignaling&Routing
ATMSignaling&Routing
FrameRelay
V5.1/V5.2
V5.1/V5.2
V5.1/V5.2
V5.1/V5.2
V5.1/V5.2
V5.1/V5.2
TCP/IP
Banyan
VB51
Banyan
VIVID
VIVID
VIVID
ATMSignaling&Routing
LANDataLinkLayer
TCP/IP
Bridge/Router
TCP/IP
WAP
Novell
WAP
Bridge/Router
WAP
WAP
WAP
X.25
X.25
TCP/IP
TCP/IP
SUN
AppleTalk
AppleTalk AppleArp, AppleTalk, EtherTalk, AARP, ADSP, AEP, AFP, ASP, ATP, DDP, NBP, PAP, RTMP, ZIP
ATM ATM Cell (AAL0-AAL5), ATM Cell NNI, ATM Cell UNI, ATM SAR,
IP Over ATM, AAL2
ATM Signaling & Routing ITU Q2931, ITU Q2971, B-ICI,
B-ISUP, IISP, PNNI Routing,
PNNI Signaling, Q.2140, Q.SAAL, SPANS, UNI 3.x, UNI 4.0,
ViVID MPOA, SPANS
Audio/Visual Over ATM ATM Circuit Emulation, DSMCC,
DVB, MPEG-2
Banyan Banyan, IPC, NetRPC, RTP,
SPP, StreetTalk, VARP, VIP
Bridge/Router BPDU, CDP, Cisco ISL, Cisco HDLC (cHDLC), Cisco SRB, DISL, DRiP, MAPOS, NSP, Proteon, RND, SSP, VTP, Wellfleet
CDMA2000 A1, A3, A7, A8, A9, A10, A11, A12, A13, A14, A15
CDPD MDLP, MNRP, SNDCP
Cellular Abis, BSMAP, BSSAP, BSSMAP,
BTSM, BTSM/LAPD, CC, DTAP, MM, O & M, RR, RLP, SMS, SMSCB, TRAU, MMS, SS
DECnet CTERM, DAP, DEC_LANBridge,
DEC_LAT, DEC_LAVC, DEC_MOP_D/L, DEC_MOP_RC,
DEC_Route, LAT, LAVC, MOP, NSP, RP, SCP, STP
Frame Relay Cascade, Frame Relay, Frame Relay Over ATM, Frame Relay Over LAPF, Frame Relay Over LLC, Frame Relay Over SNA, FRF4, FRF5, FRF8, FRF.9 (DCP),
FRF10, FRF11, FRF12, FRF16, LAPF, NNI PVC, NNI SVC, SAM Over FREther, Timeplex (BRE2),
UNI SVC
FUNI FUNI
GPRS Abis, BCC, BSSAP+, BSSGP,
CAMEL, CC, GCC, GMM/SM, GTP, LLC, MAP, MM, NS, RR, RLC/MAC, SMS, SMS(TP), SMS-CB, SNDCP, SS, TOM
GR-303 IDLC, GR-303 (IDLC/LAPD)
H.323 H.225, H.235, H.245, H.261, H.263, H225G, H.450.1, H.450.10,
H.450.11, H.450.12, H.450.2, H.450.3, H.450.4, H.450.5, H.450.6, H.450.7, H.450.8, H.450.9, H225G, RAS, RTCP, RTP, T.125, T.38, TPKT
IBM DLSw, HPR-APPN, NetBIOS, NHDR, NHRP , NLP, QLLC, SDLC, SMB, SNA, SNA 5250, SNA over SDLC,
SNA Terminology, SNARH, SNATH, SNA THO-THS, THDR
ILMI ILMI
IP Security AH, ESP, ISAKMP/IKE
IP Switching GSMP, IFMP
ISDN ISDN, LAPD
ISO ACSE, CMIP, ES-IS, FTAM, IDRP, IS-IS, ISO-IP (CLNP),
ISO-PP, ISO-SP, ISO-TP,
(ISO 8073), ISO over X.25, ROSE
LAN Data Link Layer CIF, DIS, Ethernet, FDDI,
GARP, GMRP, GVRP, LLC, SMT, SNAP, SRP, Token Ring, VLAN (802.1Q)
LAN Emulation LE 802.3, LE 802.5, LE Control
Novell BCAST, BMP, DIAG, IPX, NCP,
NDS, NLSP, Novel NetBIOS, RIPX, SAP, SER, SPX, WDOG
PPP ATCP, BACP, BAP, BCP, BSD,
BVCP, CCP, CHAP, DESE, DNCP, EAP, ECP, IPCP, IPv6CP, IPXCP, LCP, LEX, LEXCP, LQR, LZS, MPPC, Multi PPP, NBFCP, OSINLCP, PAP, PPP,
PPP Multilink, PPP-BPDU,
PPP over ATM, PPP over LAPB, PPP over LAPF, PPP over HDLC, PPPoE, SDCP, SNACP
Sigtran M2PA, M2UA, M3UA, SCTP, TALI
SMDS SIP-L3
SS7 BICC, DUP, INAP, ISUP, MTP-2,
MTP-3, Q.2140, SCCP, TCAP, TUP
SUN MOUNT, MNTv1, NFS, NLM, NSM, PMAP, RPC, RPCB, RPCB,
YP (NIS)
Tag Switching ISL, MPLS, MPLS over ATM, TDP
TCP/IP AH, ARP/RARP, ATMP, BGMP,
BGP-4, COPS, DCAP, DHCP, DHCPv6, DNS, DVMRP, EGP, EIGRP, ESP, FANP, Finger, FTP, GOPHER, GRE, HSRP, HTTP, ICMP, ICMPv6, ICP, ICPv2, IDRP,
IGMP, IGRP, IMAP4, IMPP, IP, IPv6, IPDC, IRC, L2F, L2TP, LDAP, LDP, MARS, MDTP, Megaco (ASCII + ASN.1),
Mobile IP, MZAP, NARP, NetBIOS/IP, NHRP, NTP, OSPF, PIM, POP3, PPTP, Radius, RIP2, RIPng for IPv6, RSVP, RTSP, RUDP, SCSP, SCTP, SDCP , SLP, SMPP, SMTP, SNMP, SOCKS, TACACS+, TCP, TELNET, TFTP, TRIP, UDP, Van Jacobson, VRRP, WCCP, XOT,
X-Window
UMTS AMR, BCC, BSSAP+, CAMEL, CC, FP, GCC, GMM/SM, GTP, GTP', GCP, MAC, MAP, MM, NBAP, PDCP, Q2630, RANAP, RLC, RLP, RNSAP, RRC, SMS, SMS(TP), SNDCP,IuUP, SMSCB, BMC, MTP3B, RR, SS
UNIX Rexec, Rlogin, Rprint, Rshell,
Rwho
V5.1/V5.2 LAPV5, V5, V5-BCC, V5-Control,
V5-Link Control, V5-Protection, V5-PSTN
VB51
VB51
VIVID
VIVIDarm, VIVIDbme, VIVIDccp
VoDSL
ELCP, LAPV5DL, LES-PSTN, (VoATM)
VoIP AVAYA (Skinny), G729, G723.1, G711, Megaco (H.248),
Megaco over ATM, MGCP, PROXY (Skinny), RVP over IP, SAP v2, SDP, SIP, Skinny, SGCP
WAP WCMP, WDP, WSP, WTLS, WTP
X.25 HDLC, IP Over HDLC,
IPARSE over X.25 over LAPB, LAPB, MLP,
SAM Over X.25 Over LAPB, X.25, X.75
XNS IDP, PEP, RIP, SPP

REFERENCES & RESOURCES