AimValley proposes TSoP standard

HILVERSUM, The Netherlands, August 30, 2012 –AimValley has published an IETF draft standard, disclosing the Transparent SDH/SONET over Packet (TSoP) technology.

This circuit emulation method is applied in the TSoP Smart SFP module that was jointly developed by AimValley and OE‑Solutions and which has recently been launched. The TSoP IETF draft standard is written in collaboration with experts from Alcatel‑Lucent.

The essence of the TSoP method is that an STM‑N or OC‑N client signal is transported completely transparent in a Pseudowire (PW) over a Packet Switched Network (PSN): The bits that are input on one edge of the PSN are exactly the same as the bits that are output on the other edge. This transparency extends to the timing properties of the client signal. Actually, to transport an STM‑N/OC‑N client signal transparently, only its bit rate is relevant to the PW and PSN layers. This implies that SONET/SDH differences disappear.

Although circuit emulation techniques are routinely deployed in the network for a number of years, there was, until now, no method standardized for the emulation of complete STM‑N or OC‑N circuits in a transparent manner over MPLS and Ethernet packet networks. Alcatel‑Lucent and AimValley have taken the initiative to close this gap by publishing an IETF draft standard that describes such a method in a document provisionally titled: draft-manhoudt-pwe3-tsop.

While it seems quite obvious to transport STM‑N/OC‑N signals in a transparent fashion, the single existing standard on this subject (IETF RFC 4842) only specifies the transport of the virtual container(s) inside the STM‑N/OC‑N signal over a PSN. This approach effectively blocks transport of the embedded channels for network management, automatic protection switching and a number of other maintenance functions in the STM‑N/OC-N overhead that are of key importance to an operator. This explains the interest in an alternative method that is less intrusive.

“The TSoP Smart SFP processes the STM‑N/OC‑N signal fully transparent, maintaining payload structure, protection protocols and synchronization end-to-end; this simplifies the configuration and service turn-up of STM‑N/OC‑N connections across a packet network,” says Pieter de Boer, managing director at AimValley. “The integration of TSoP into an SFP greatly reduces system and network complexity, and offers lower carbon footprint while generating CAPEX & OPEX savings.”

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About AimValley

AimValley, founded in 2003, helps companies to get a grip on their telecom and data networking technologies. The company does so by providing state-of-the-art technological solutions for telecommunications and data communication systems providers. AimValley offers a full range of system level services including product definition and architecture, software design, systems testing, hardware design, and factory introduction. From stand-alone consultancy to comprehensive turnkey solutions. AimValley builds on its experience at leading telecom suppliers and technology research labs. More information via