Chapter 2 Getting Started
Implementing LVS
SPA400 Hardware
Figure 2-5 SPA400 Back Panel
The SPA400 provides the following interfaces (from left to right):
•USB—Use this to connect the SPA400 USB voicemail module containing voicemail prompts and provides the storage location for saving voice mailbox messages.
•Ethernet—Connect to the SPA9000 through the appropriate switch.
•Line 1 to 4—Connect to the telephone line provisioned by your PSTN provider.
•Power—Connect to the power supply.
Figure 2-6 SPA400 Front Panel
The SPA400 provides the following LEDs, from left to right:
•Power—Steady green: powered on and connected to the Internet. Flashing: not connected to the Internet, booting, or upgrading firmware.
•Status—Steady green: SPA400 registered to the SPA9000. Flashing: SPA400 not registered.
•Line 1-4—Steady green: line is active; flashing: ringing; off: idle.
•Ethernet—Steady green: active connection. Flashing: indicates traffic.
•USB—Steady green: USB voicemail module registered. Off: no module detected.
Bandwidth Requirements
Depending on how you have your IP phones configured, each call requires 55 to 110 kbps in each direction. Therefore, using G.729 as the voice codec setting, and with an average business-grade broadband Internet connection supporting 1.5 Mbps downstream and 384 kbps upstream, a total of seven
(7)simultaneous conversations can be reliably supported with adequate bandwidth available for file downloads.
Linksys recommends using the SPA9000 with QoS-capable networking equipment that can prioritize the VoIP application traffic. QoS features are available on many Linksys data networking switches and routers. A QoS-enabled router prioritizes the packets going upstream to the ISP. Table 2-1illustrates the bandwidth budget using different codecs.
| Linksys SPA9000 Administrator Guide |
2-6 | Document Version 3.01 |