Peter Southwick is a Senior Network Engineer at Proteus Networks, providing both professional services support and training for Proteus Networks customers. He is a JNCI, holds JNCIE-M #473 and other Juniper certifications in routing and security. He is an author of Telecommunications: a Beginners Guide, co-author of ISDN: Concepts, Facilities and Services (both published by McGraw Hill), and contributing author to The Handbook of Local Area Networks (CRC Press).