XENPAK
{{Use American English|date=June 2023}}
XENPAK is a multisource agreement (MSA), instigated by Agilent Technologies and Agere Systems, that defines a fiber-optic or wired transceiver module which conforms to the 10 Gigabit Ethernet (10GbE) standard of the Institute of Electrical and Electronics Engineers (IEEE) 802.3 working group. The MSA group received input from both transceiver and equipment manufacturers during the definition process. XENPAK has been replaced by more compact devices providing the same functionality.
History
The XENPAK MSA was publicly announced on March 12, 2001 and the first revision of the document was publicly released on May 7, 2001. The most recent revision of the MSA, Issue 3.0, was published on September 18, 2002. The result covered all physical medium dependent (PMD) types defined by the IEEE at that time for 802.3ae 10GbE.{{cite web |title= Welcome to Welcome to XENPAK.org |url= http://www.x2msa.org/ |archive-url=https://web.archive.org/web/20081218123926/http://www.xenpak.org/ |archive-date= December 18, 2008 |access-date= May 7, 2011 }}
Although the XENPAK agreement received early support, its modules were thought to be overly large for high-density applications.{{cite news |title= Sizing Up Xenpak |author= Pauline Rigby |work= Light Reading |date= January 30, 2002 |url=http://www.lightreading.com/document.asp?doc_id=11370 |access-date= May 7, 2011 }} {{Asof |2010}}, vendors generally changed to use XFP modules for longer distances, and Enhanced small form-factor pluggable transceivers, known as SFP+ modules, for higher densities.{{cite news |title= Mature Components Market Drives 10GE Rollout |author= Simon Stanley |work= Light Reading |date= April 13, 2011|url=http://www.lightreading.com/document.asp?doc_id=206752 |access-date= May 7, 2011 }}
The newer modules have a purely serial interface, compared to the four "lane" XAUI interface used in XENPAK.{{cite web |title= SFF-8431 Specifications for Enhanced Small Form Factor Pluggable Module SFP+ Revision 4.1 |date= July 6, 2009 |url= http://ftp.seagate.com/sff/SFF-8431.PDF |access-date= May 9, 2011 }}
Description
XENPAK modules were supplied for physical layer interfaces supporting multi-mode and single mode fiber optic cables and InfiniBand copper cables with connectors known as CX4. Transmission distances vary from {{convert |100 |m}} to {{convert |80 |km}} for fiber and up to {{convert |15 |m}} on CX4 cable. Newer XENPAKs using the 10GBase-LX4 standard operated using multiple wavelengths on legacy multi-mode fibers at distances of up to {{convert |300 |m}}, eliminating the need to reinstall cable in a building when upgrading certain 1 Gbit/s circuits to 10 Gbit/s.
Replacement form factors
The XENPAK form factor was initially supported by numerous network equipment manufacturers and module makers. However, advances in technology led to more compact form factors for 10 Gigabit Ethernet applications. Soon after the standard was introduced in 2001, two related standards emerged: XPAK and X2. These two standards have the same electrical interface as XENPAK (known as XAUI) but different mechanical properties.
The XPAK group was announced on March 19, 2002, first published their specification on May 24, 2002, and version 2.3 on August 1, 2003.{{cite web |title= Welcome to the XPAK MSA home page |url= http://www.x2msa.org/ |archive-url=https://web.archive.org/web/20040729111650/http://xpak.org/ |archive-date= July 29, 2004 |access-date= May 7, 2011 }}
The X2 group was announced on July 22, 2002, and published their specification on February 13, 2003.{{cite web |title= Welcome to X2MSA.org |url= http://www.x2msa.org/ |archive-url=https://web.archive.org/web/20081104051430/http://www.x2msa.org/ |archive-date= November 4, 2008 |access-date= May 7, 2011 }}
Issue 3.0 of the XENPAK MSA was transferred to the Small Form Factor committee as document INF-8474 on September 18, 2002.{{cite web |title= INF-8474i Specification for Xenpak 10 Gigabit Ethernet Transceiver Rev 3.0 |date= September 18, 2002 |url= http://ftp.seagate.com/sff/INF-8474.PDF |access-date= May 7, 2011 }}
Use with modern optics
As of 2014, adapters are available that permit use of any modern SFP+ 10 Gbit/s optic in a XENPAK interface.{{Cite web|title=XENPAK to SFP+ adapter|url=https://www.flexoptix.net/en/10-gigabit-xenpak-sfp-plus-adapter.html|access-date=2020-09-14|website=www.flexoptix.net|language=en}}