What the syllabus asks you to cover
Digital and analog switching, soft switching, Routing and Signaling.
Start here for the core ideas. A dedicated GitBook topic page was not available; this original guide is introductory. Use the syllabus checklist and references below to study the remaining details.
Follow the connection through the network
Circuit switching reserves an end-to-end resource for a session; packet switching shares resources among packets. Analog versus digital describes representation or processing, while circuit versus packet describes resource organization. These pairs should not be treated as synonyms.
Distinguish control from transport
Signalling establishes, manages and releases sessions or resources. Routing chooses paths. A softswitch separates selected call-control functions from the media transport infrastructure. A complete explanation should identify both the control messages and the path carrying user information.
Try it
In a packet network, two users can share a link even when their packets take turns using it. Variable queueing delay is one consequence; an application may need buffering or quality-of-service measures.
Check your understanding
Draw a simple call setup and label signalling and user traffic. Compare blocking in a circuit system with congestion in a packet system. Continue with routing, common-channel signalling and switching architectures.
Pause and recall
Without looking back, explain the main idea, recall a key definition or formula, and describe when it applies. Include assumptions and units where relevant. Revisit any step you could not explain.