Here are some thing that is nice to know. Of course check the blueprint to see what is recommended reading.
Cisco Unified IP Phone Firmware Distribution Methods
Table 1. Summary of Distribution Models
| Peer Firmware Sharing | Load Server | Traditional TFTP | |
|
Advantages |
• Hierarchy is automatic
• One download per phone model on a subnet
• Uses TCP
• Fails back to TFTP
• Speeds up LAN upgrades
• Reduces TFTP CPU load during upgrade
|
• Has same download time as LAN image distribution
• Distributes TFTP load over multiple TFTP servers
|
• Proven distribution
• Default behavior
|
|
Disadvantages |
• Must be enabled on each phone
• Hierarchy is formed for each phone model
• Hierarchy is limited to subnet
|
• IP must be set on each phone
• Administrator must manually file copy to load server
• No failback to TFTP on error
• More prone to user error
|
• High-bandwidth requirements
• Multiple requests for same file
• High CPU usage on TFTP server
|
Link : http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/uc_system/design/guides/videodg/vidguide/qos.html
ISDN Q-Interface Signaling Protocol Q.931 Tunneling over the IP Network
