The Cisco ® Interface Flexibility (I-Flex) design combines shared port adapters (SPAs) and SPA interface processors (SIPs), taking advantage of an extensible design that helps enable service prioritization for voice, video, and data services. Enterprise and service provider customers can take advantage of improved slot economics resulting from modular port adapters that are interchangeable across Cisco routing platforms. The Cisco I-Flex design maximizes connectivity options and offers superior service intelligence through programmable interface processors that deliver line-rate performance. Cisco I-Flex enhances speed-to-service revenue and provides a rich set of quality of service (QoS) features for premium service delivery while effectively reducing the overall cost of ownership. This data sheet contains the specifications for the Cisco 2-, 5-, 8-, and 10-Port Gigabit Ethernet Shared Port Adapters, Version 2

The Cisco 2-, 5-, 8-, and 10-Port Gigabit Ethernet SPAs are available on high-end Cisco routing platforms, offering the benefits of network scalability with lower initial costs and ease of upgrades. The Cisco SPA/SIP portfolio continues the company's focus on investment protection along with consistent feature support, broad interface availability, and the latest technology. The Cisco SPA/SIP portfolio allows deployment of different interfaces (Packet over SONET/SDH [PoS], ATM, Ethernet, etc.) on the same interface processor.

Gigabit Ethernet interfaces are commonly used for interconnecting routers or other devices within a central office or data center or in a metropolitan-area network (MAN). Cisco offers an extensive variety of 1000BASE-X Gigabit Ethernet SPAs to meet customers' needs for various applications. With Cisco Gigabit Ethernet SPAs, you can mix-and-match SPA ports with other types of interfaces in the same slot. Each SPA provides standards-based Gigabit Ethernet implementation for compatibility and interoperability.

In addition to the two Small Form-Factor Pluggable (SFP)-based Gigabit Ethernet ports, two additional built-in RJ-45 ports are provided on the 2-port Gigabit Ethernet SPA, Version 2. A combination of these Gigabit Ethernet ports is permitted, limited to a total of 2 Gigabit Ethernet ports (both copper, both optical, or one copper and one optical).

Applications
The Cisco Gigabit Ethernet SPAs can be used in multiple applications, including:

- Inter- and intra-point of presence (POP) aggregation
- Residential triple play (data, voice, and video)
- Metro Ethernet services
- Converged residential and business services
- Internet peering