CCNP Voice CIPT1 642-447 Quick Reference: Single-Site On-Net Calling
Endpoints
This section focuses on the features and characteristics of the H.323, Skinny Client Control Protocol (SCCP), and Session Initiation Protocol (SIP) endpoints that interwork with CUCM.
Endpoint Support
Cisco IP phones support SCCP and SIP and split into two categories:
- Type A phones: 7905, 7912, 7940, and 7960
- Type B phones: Most other modern Cisco phones
Cisco also has a software-based phone: the Cisco IP Communicator. Other Cisco endpoints are the Cisco Unified IP Phone 7985 (a desktop video phone), the Cisco Unified IP Phone 7920 and 7921 models (Wi-Fi phones), and the Cisco Unified IP Phone 7935 and 7936 models (conference stations). Third-party products are available for all supported protocols.
Feature Support
Use these categories to define feature support:
- SCCP: A Cisco proprietary protocol; offers a rich set of telephony features
- Standard SIP or H.323: Limited feature support when compared to SCCP
- Cisco Unified CM SIP support for Cisco IP Phones: Approximates the number of SCCP-supported features
Functions Found with Cisco IP Phones
- Cisco Discovery Protocol (CDP)
- DHCP
- MAC address-based device identification
- TFTP
- Power over Ethernet (PoE)
- PC port
Cisco SCCP IP Phone Startup Process
- Step 1. The phone obtains power from the switch.
- Step 2. The phone loads the stored image.
- Step 3. The VLAN is configured using CDP.
- Step 4. The phone obtains an IP address using DHCP (option 150) or is assigned statically.
- Step 5. The phone requests the configuration file.
- Step 6. The phone checks load file.
- Step 7. The phone registers with CUCM.
Cisco SIP Phone Startup Process
The first four steps are the same as for the Cisco SCCP IP Phone startup. Then these steps occur:
- Step 1. The phone boots and tries to download a control (CTL) file.
- Step 2. The phone requests its SEP<mac>.cnf or the default configuration file from the Cisco TFTP server.
- Step 3. The phone requests the .Loads file.
- Step 4. If configured the phone downloads the dial-rule file.
- Step 5. The phone registers with the highest priority CUCM server.
H.323 Phone Configuration Requirements
The H.323 phone has to be added to the CUCM with IP address and directory numbers specified. The H.323 endpoint then has to be configured to point to the IP address of the CUCM.
Following are features not supported for H.323 phones:
- MAC address registration
- Phone button templates
- Softkey templates
- Certain telephony features such as IP phone services and Cisco Unified Presence, Cisco Unified Video Advantage, Call Pickup, and Barge.
Third-Party SIP Phone Configuration Requirements
- Step 1. Configure the end user in CUCM.
- Step 2. Add the third-party SIP phone in CUCM, and configure its directory numbers.
- Step 3. Associate the third-party SIP phone with the end user configured in Step 1.
- Step 4. Configure the third-party SIP phone with the IP address of CUCM, end-user ID, digest credentials, and directory numbers.
Third-party SIP phones use digest authentication to register to the CUCM .
Features not supported for third-party SIP endpoints follow:
- MAC address registration
- Phone button templates
- Softkey templates
- Certain telephony features such as IP phone services, Cisco Unified Presence, Cisco Unified Video Advantage, Call Pickup, and Barge.