Service providers use other people`s transportation systems. This is very common, even the largest networks use other transport and transport infrastructure of other modes of transport, especially outside their main site. For example, the operator could offer services primarily in the United States, but expand its network to Europe. The Unenforceable Use Right (IRU) is a kind of permanent telecommunications lease that cannot be cancelled between the owners of a communication system and a customer of that system. The word „unenforceable“ means „not being able to be declared or unreported or cancelled.“ The client acquires the right to use a certain amount of the system`s capacity for a number of years. IRU contracts are almost always long-term and usually take 20 to 30 years. The communication system can be a wire cable. B, for example, an underwater communication cable, a fibre optic cable or a satellite. An IRU owner may use unconditionally and exclusively the corresponding capacity of the IRU`s network of beneficiaries during the specified period. Think about it, if you rent an apartment, sign a contract with the landlord as a tenant. You cannot rent this apartment to someone else.
It`s a bit like leasing. But if you are the owner, you can rent it to anyone you want. This is an example of unachievable user rights. The Impractical Right of Use (IRU) is a permanent contract, which cannot be cancelled between the owners of a cable and a customer of this cable system. Cable is usually a fiber optic cable because fiber optics can transmit more data than any other type of media. The IRU „means the exclusive, unlimited and unworkable right to use the relevant capacity (including equipment, fibre or capacity) for any legal purpose.“  It refers to the bandwidth purchased, for example after the sealing of a submarine wiring system at the end of construction, and the maintenance contract (C-MA) between the owners. This is a way for homeowners to use unused capacity or any unused capacity after the system is put into service. The parties agree that the IRU segments were built in advance and that the use of the Coudersport/Bucktail fibre optic cable „AS IS,“ „WHERE IS“ and „WITH ALL FAULTS“ will be granted to the terms and conditions of the IRU agreement; provided, however, that the above does not limit the rights and obligations of Adelphia, TWNY or Comcast under the respective asset chasing agreements or otherwise modify them.
In short, the purchase of an IRU gives the buyer the right to use certain capabilities on a telecommunications system, including the right to lease that capability to someone else. Small businesses that need a rental line between, say, London and New York do not buy IRU — they lease capacity from a telecommunications company that can itself lease more capacity from another company (and so on) until the end of the contract chain there is a company that has an IRU or has a complete wiring system. In order to have a good understanding of SP networks, you can check out my new book client „Service Provider Networks Design and Architecture Perspective „, which can buy IRU and lease its capacity to other companies.