Multilink PPP with Link Fragmentation Interleave

Multilink PPP with link fragmentation interleave (MLPPP with LFI) allows large packets to be multilink-encapsulated and fragmented into smaller packets, thus ensuring that voice packets are transmitted without delay; small real-time packets, which are not multilink-encapsulated, are transmitted between fragments of the large packets. The interleaving feature also provides a special transmit queue for the smaller, delay-sensitive packets, enabling them to be transmitted earlier than other flows.

You should configure MLPPP with LFI if you have a dialer, an ISDN PRI or BRI interface, or a virtual template, and either of the following:

Point-to-point connections using PPP encapsulation

Links slower than 2 Mbps

Note Do not use MLPPP with LFI on links faster than 2 Mbps.

Configuring MLPPP with LFI

To configure MLPPP with LFI on a dialer, ISDN PRI or ISDN BRI interface, or a virtual template, you must first configure MLPPP with LFI on the interface or template by entering the following commands while in interface configuration mode:

Router(config-if)# encapsulation ppp

Router(config-if)# ppp multilink

Router(config-if)#ppp multilink interleave

Optionally, configure a maximum fragment delay:

Router(config-if)#ppp multilink fragment-delay milliseconds

You can also reserve a special queue for real-time packet flows to specified destination User Datagram Protocol (UDP) ports, allowing real-time traffic to have higher priority than other flows. You need the following command only if you have not configured RSVP:

Router(config-if)#ip rtp reserve lowest-UDP-port range-of-ports

For virtual templates only, apply the virtual template to the multilink bundle:

Router(config-if)#multilink virtual-template 1

To create a virtual template interface, enter the following interface virtual-templateglobal configuration command:

Router(config)# interface virtual-template 1

Real-Time Transport Protocol Header Compression

Real-Time Transport Protocol (RTP) header compression on a PPP, HDLC, or similar serial interface compresses the packet header to reduce network overhead.

You should configure RTP header compression on a serial interface if you have either of the following:

Links slower than 2 Mbps

A need to conserve bandwidth

Note Do not use RTP header compression on links faster than 2 Mbps.

Configuring RTP Header Compression

Enable RTP header compression at both ends of the serial link by entering the ip rtp header-compressioninterface configuration command:

Router(config-if)#ip rtp header-compression

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Cisco Systems 1760 Multilink PPP with Link Fragmentation Interleave, Real-Time Transport Protocol Header Compression

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.