Figure 22 A Network Using ISDN BRI Voice Interfaces

 

Router A: Cisco 1760

 

Router B: Cisco 1760

BRI NT

WAN/IP

BRI TE

Network

interface

 

interface

PBX

 

PSTN

 

 

60960

Configuring the BRI Layer 1

At the BRI Layer 1, you can configure each port of the VIC to operate in NT (clock source) or TE (clock slave) mode by using the IOS isdn layer1-emulatecommand in interface configuration mode:

isdn layer1-emulate {network user}

where network enables the VIC to operate in the NT mode, and user enables it to operate in the TE mode. The default setting for each port is the TE mode.

Configuring the ISDN Protocol

Depending on your ISDN switch type, the Layer 2 protocol may be configured to operate in NT or TE mode. To do this, use the isdn protocol-emulatecommand in interface configuration mode:

isdn protocol-emulate {network user}

where network enables the ISDN Layer 2 to operate in the NT mode, and user enables it to operate in the TE mode. The default setting is the TE mode.

Note The configurations of Layer 1 and Layer 2 are independent of each other. For example, you can set the Layer 1 operating mode to NT and set the Layer 2 to TE.

Turning the Line Power On/Off

To control the line power (phantom power only) being supplied to a connected device, use the line_power command in interface configuration mode:

line_power

no line_power

The line_power and no line_power commands are valid only for a BRI port operating in NT mode. If a port is equipped with hardware to supply line power, using these commands will activate or deactivate line power provision from that port.

Setting the Network Clock Priority

If a port is operating in TE mode, you can set the clock priority for that port. The clock priority determines whether the external clock on the ISDN line or the internal clock on the system board takes control. To change the clock priority, use the network-clock-prioritycommand in interface configuration mode:

network-clock-priority {high low}

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Cisco Systems 1760 quick start Configuring the BRI Layer, Configuring the Isdn Protocol, Turning the Line Power On/Off

1760 specifications

The Cisco Systems 1760 series routers are part of Cisco’s popular line of integrated services routers, designed primarily for small to medium-sized businesses and branch offices. The 1760 series was introduced to provide robust connectivity and routing solutions that facilitate secure and reliable networking. Aimed at offering flexibility, these routers integrate multiple functionalities to enhance operational performance.

One of the main features of the Cisco 1760 router is its modularity. It supports various interface and service modules that allow for customization based on specific networking needs. This modular design enables businesses to expand their networking capabilities over time without necessitating a complete hardware overhaul. The router typically comes equipped with two WAN slots and numerous interface options, including Fast Ethernet and serial interfaces.

The 1760 series routers also support advanced security features, providing businesses with a secure environment for their data transmissions. Built-in firewall capabilities, along with support for Virtual Private Network (VPN) protocols, ensure that sensitive information remains protected. Furthermore, the integration of IPsec and MPLS security features assists organizations in maintaining secure and scalable connections across diverse networks.

Another characteristic of the Cisco 1760 is its support for various technologies, including Quality of Service (QoS). QoS functionality allows network administrators to prioritize traffic, ensuring that critical applications receive the bandwidth they require while minimizing latency. This ability is particularly valuable in environments where voice, video, and essential data applications compete for resources.

The router’s ease of management is also noteworthy. With Cisco’s IOS (Internetwork Operating System), the 1760 provides a user-friendly interface allowing for straightforward configuration and monitoring. The simplicity in managing the network devices helps reduce the burden on IT personnel and enhances overall operational efficiency.

Further enhancing the router’s capabilities is its support for voice over IP (VoIP) applications, making it an ideal choice for organizations looking to implement modern telephony solutions. The ability to support multiple voice channels while maintaining adequate data throughput positions the 1760 as an attractive option for businesses transitioning to unified communications.

In summary, the Cisco Systems 1760 series routers exhibit a harmonious blend of modularity, robust security, traffic management, and VoIP support. They effectively meet the demands of modern networking environments, making them a reliable choice for organizations aiming to streamline operations while ensuring secure connectivity. With their adaptable design, these routers can serve as a powerful backbone for enterprise networking needs.