INTERNATIONAL  TELECOMMUNICATION  UNION

		     ITU-T RECOMMENDATION SUMMARY


Rec. No. : L.12

Title :	Optical fibre joints

Study Group : VI - Outside Plant

Version : New

Date of adoption : 1992

Notes :	

Optical fibre cables have become common in telecommunications for 
trunk, undersea and feeder routes and are now expanding into the 
subscriber and indoor sections of the network. They are installed in 
all environments: aerial, duct, cable tunnels, direct buried and 
on-premises. Thus, optical fibre cables are exposed to all of the 
hazards that copper cables are. An important part of any installed 
optical fibre cable system is the fibre joint, which can have a great 
influence on the transmission quality and maintenance costs. The loss 
of a joint can equal the insertion loss of as much as one half to one 
kilometre of fibre.

Recommendation L.12 advises on the mechanical, environmental and 
optical characteristics of optical fibre joints, and advises on 
suitable testing methods. Further information is provided in the CCITT 
Manual "Construction, installation, jointing and protection of optical 
fibre cables".

Recommendation L.12:

	-   refers to the jointing of optical fibre cables that are 
used for telecommunications networks, in duct, tunnel, buried, aerial, 
and underwater installations;

	-   deals with loss factors of optical fibre joints in 
multimode graded index and single-mode fibres;

	-   deals with optical and physical characteristics of optical 
fibre joints concerned;

	-   acknowledges there are two basic types of optical fibre 
joints (fusion and mechanical) with numerous design variations;

	-   advises on appropriate test methods for optical fibre joints.



To order the complete text of this Recommendation, please use the 
Order Form for ITU-T Recommendations. An electronic version of this 
form is available on ITUDOC (Winword 2.0: UPI=ITU-5265; ASCII: UPI=ITU-2488).