Passport Carrier Release (PCR) is a version of the Passport Switch (now Multiservice Switch) software designed to run in telecommunications carrier environments. It was formerly developed by

Nortel Nortel Networks Corporation (Nortel), formerly Northern Telecom Limited, was a Canadian Multinational corporation, multinational telecommunications and data networking equipment manufacturer headquartered in Ottawa, Ontario. It was founded in ...

. After the sale in 2009 of most Nortel's assets, the passport SW is still used in several products of

Alcatel-Lucent Alcatel-Lucent S.A. () was a multinational telecommunications equipment company, headquartered in Boulogne-Billancourt, Paris, France. The company focused on Fixed line telephone, fixed, Mobile phone, mobile and telecommunications convergence, ...

Ericsson (), commonly known as Ericsson (), is a Swedish multinational networking and telecommunications company headquartered in Stockholm, Sweden. Ericsson has been a major contributor to the development of the telecommunications industry and is one ...

and

Kapsch The Kapsch Group, headquartered in Vienna, Austria, is an international corporation specializing in telematics, information technology and telecommunication. History and operations In September 1892, Johann Kapsch (1845–1921) founded a precisi ...

. The passport products are now part of Ericsson's PPX products under IP Networking. The Ericsson PPX products can be found at the following link.

Technologies

Internally, PCR is largely built up of custom applications on top of a

VxWorks VxWorks is a real-time operating system (or RTOS) developed as proprietary software by Wind River Systems, a subsidiary of Aptiv. First released in 1987, VxWorks is designed for use in embedded systems requiring real-time, Deterministic system, ...

kernel. A benefit of the software is that it is completely

modular Module, modular and modularity may refer to the concept of modularity. They may also refer to: Computer science and engineering * Modular design, the engineering discipline of designing complex devices using separately designed sub-components ...

and can load components to Passport control processors (CPs) and function processors (FPs) on an as-needed basis. FPs (also known as line cards) each run their own instance of the Operating System, and as such can be rebooted without the need to take the entire switch out of service, for example due to a software failure. As well, as would be expected, entire cards can be replaced while the system is hot, thus minimizing downtime due to hardware failure.

OAM and provisioning

PCR consists of a custom OAM interface that is highly object oriented. This reflects the modular nature of the operating system. The core component when provisioning IP networks is the Virtual Router (however, a Passport switch can act in more than IP environments). Interfaces are provisioned as "application" objects, which are then in turn connected to Protocol Ports on a Virtual Router. It is best to consider the environment in which provisioning occurs to be

object oriented Object-oriented programming (OOP) is a programming paradigm based on the concept of '' objects''. Objects can contain data (called fields, attributes or properties) and have actions they can perform (called procedures or methods and impleme ...

, in the sense that the behaviour of the router is defined based on which objects are instantiated and how they are related. Note that there is a change in this paradigm noticeable in recent releases of PCR --

MPLS Multiprotocol Label Switching (MPLS) is a routing technique in telecommunications networks that directs data from one node to the next based on labels rather than network addresses. Whereas network addresses identify endpoints, the labels identi ...

, for example, now resides on an object called simply a Router with built-in IP features. This provisioning approach is more similar to that of

Cisco Cisco Systems, Inc. (using the trademark Cisco) is an American multinational digital communications technology conglomerate corporation headquartered in San Jose, California. Cisco develops, manufactures, and sells networking hardware, s ...

Juniper Networks Juniper Networks, Inc. is an American multinational corporation headquartered in Sunnyvale, California. The company develops and markets networking products, including Router (computing), routers, Network switch, switches, network management so ...

Drawbacks

Unfortunately, at this time the OAM interface is unable to select which components are to be loaded on the fly. For example, if Multi-link

Point-to-Point Protocol In computer networking, Point-to-Point Protocol (PPP) is a data link layer (layer 2) communication protocol between two routers directly without any host or any other networking in between. It can provide loop detection, authentication, transmissio ...

(PPP) is a required feature, before this feature can be used the CP and the FP hosting the MLPPP interface must have the mlppp feature loaded. As well, the vast array of objects available to an operator can be daunting, especially for an individual starting out with Nortel Passport switches for the first time. As well, built in documentation leaves much to be desired (thus not helping the first-time operator), and tab completion features are non-existent (though some objects and parameters have shorthand names, for example the Virtual Router component can simply be known as a Vr).

Versioning

PCR releases are assigned a release code, usually of the form CG##X, where ## is a two digit number and X is a letter, usually referring to a patch code or revision code. The current release is PCR 10.1.1.

References

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External links