350-801 cheat sheet

Exam at a glance

Domain weightings

How much of the exam each domain covers. Spend your study time in proportion — the heavier the domain, the more questions you'll see.

Key terms

Cisco Unified Communications Manager

Cisco Unified Communications Manager (CUCM, or Unified CM) is the on-premises IP telephony call-processing platform that handles registration, call routing, and features. CLCOR's largest domain centers on CUCM call control.

SIP

Session Initiation Protocol (SIP) is the signaling protocol that establishes, modifies, and tears down voice and video sessions. CLCOR covers SIP among the protocols and endpoints of collaboration.

Dial Plan

A Dial Plan defines how CUCM routes calls using route patterns, partitions, calling search spaces, and translations. CLCOR covers dial-plan configuration under on-premises call control.

Voice Gateway

A Voice Gateway connects the IP telephony network to the PSTN or legacy systems, converting between VoIP and TDM/analog. CLCOR covers voice gateways and their configuration.

SBC

A Session Border Controller (SBC), such as Cisco Unified Border Element (CUBE), secures and controls SIP trunk connections at the network edge. CLCOR covers SBCs and SIP trunking to service providers.

Webex

Cisco Webex is the cloud collaboration suite for meetings, calling, and messaging that integrates with on-premises deployments in hybrid designs. CLCOR covers Webex under cloud and hybrid services.

Webex Calling

Webex Calling is Cisco's cloud-based phone system (UCaaS) that can replace or coexist with on-premises CUCM. CLCOR covers Webex Calling in the cloud and hybrid services domain.

Expressway

Cisco Expressway provides secure firewall traversal and mobile/remote access (MRA) so off-network endpoints can register to CUCM without a VPN. CLCOR covers Expressway for hybrid connectivity.

QoS

Quality of Service (QoS) classifies, marks, and queues traffic so real-time voice and video get priority and low latency. CLCOR's Media and QoS domain covers marking and queuing for collaboration media.

DSCP

Differentiated Services Code Point (DSCP) is the marking in the IP header that signals a packet's QoS treatment, such as EF for voice. CLCOR covers DSCP marking for media traffic.

LLQ

Low Latency Queuing (LLQ) adds a strict-priority queue to CBWFQ so voice traffic is served ahead of other classes. CLCOR covers LLQ configuration (class map, policy map, service policy) for media.

RTP

Real-time Transport Protocol (RTP) carries the actual voice and video media stream between endpoints, with SRTP adding encryption. CLCOR covers media protocols under protocols and endpoints.

Codec

A Codec (such as G.711, G.729, or Opus) encodes and compresses voice or video for transport, trading bandwidth against quality. CLCOR covers codecs and their negotiation between endpoints.

MRA

Mobile and Remote Access (MRA) lets Cisco endpoints register to CUCM securely from outside the corporate network through Expressway, without a VPN. CLCOR covers MRA in hybrid and remote deployments.

Media Resources

Media Resources are CUCM services such as conference bridges, transcoders, and MOH that manipulate or mix media streams. CLCOR covers configuring media resources under call control and media.