The Unidirectional Lightweight Encapsulation (ULE) is a Data link layer

Data link layer

The data link layer is layer 2 of the seven-layer OSI model of computer networking. It corresponds to, or is part of the link layer of the TCP/IP reference model....

 protocol for the transportation of network layer packets over MPEG transport streams.

Because of the very low protocol overhead, it is especially suited for IP over Satellite services (where every bit counts). Such a system is for example DVB-S

DVB-S

DVB-S is an abbreviation for Digital Video Broadcasting — Satellite; it is the original Digital Video Broadcasting forward error coding and demodulation standard for satellite television and dates from 1994, in its first release, while development lasted from 1993 to 1997...

. However, ULE can also be used in the context of DVB-C

DVB-C

DVB-C stands for Digital Video Broadcasting - Cable and it is the DVB European consortium standard for the broadcast transmission of digital television over cable...

 and DVB-T

DVB-T

DVB-T is an abbreviation for Digital Video Broadcasting — Terrestrial; it is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in the UK in 1998...

, theoretically in every system which is based on MPEG transport streams (e.g., ATSC).

ULE has been engineered by the IP over DVB (ipdvb) working group of the Internet Engineering Task Force

Internet Engineering Task Force

The Internet Engineering Task Force develops and promotes Internet standards, cooperating closely with the W3C and ISO/IEC standards bodies and dealing in particular with standards of the TCP/IP and Internet protocol suite...

 (IETF) and has been standardized in RFC 4326.

Another encapsulation method is Multiprotocol Encapsulation

Multiprotocol Encapsulation

Multiprotocol Encapsulation, or MPE for short, is a Data link layer protocol definedby DVB which has been published as part of ETSI EN 301 192...

 (MPE) which was developed and standardized by the DVB project.

See also

• IP over DVB
  IP over DVB
  IP over DVB or IP over MPEG implies that Internet Protocol datagrams are transferred over the MPEG transport stream, and are distributed using some digital television system, for example DVB-H, DVB-T, DVB-S or DVB-C.-Application examples:...
  
  
• MPEG transport stream
• DVB
• MPEG-2
  MPEG-2
  MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission...
  
  
• Multiprotocol Encapsulation
  Multiprotocol Encapsulation
  Multiprotocol Encapsulation, or MPE for short, is a Data link layer protocol definedby DVB which has been published as part of ETSI EN 301 192...
  
   (MPE)
• Datacasting
  Datacasting
  Datacasting is the broadcasting of data over a wide area via radio waves. It most often refers to supplemental information sent by television stations along with digital television, but may also be applied to digital signals on analog TV or radio...
  
  
• Internet Protocol Datacasting (IPDC) for DVB-H
  DVB-H
  DVB-H is one of three prevalent mobile TV formats. It is a technical specification for bringing broadcast services to mobile handsets. DVB-H was formally adopted as ETSI standard EN 302 304 in November 2004. The DVB-H specification can be downloaded from the official DVB-H website...
  
  
• UDcast
  UDcast
  UDcast is a provider of solutions enabling full Internet Protocol over broadcast media, in the areas of IP networks over satellite andservers for DVB-H, DVB-SH, ATSC and WiMAX standards compliant television on mobile networks....
  
  
• Interactive television
  Interactive television
  Interactive television describes a number of techniques that allow viewers to interact with television content as they view it.- Definitions :...
  
  

Implementations

Software:
Linux Kernel,  
ulenet for Windows XP,  

The ipdvb Working Group maintains a list of ULE implementations.