New EtherSwitch service modules on ISR G2

Second Generation Integrated Services Router

This blog will discuss the Power over Ethernet (PoE) service modules (SM) supported in the second generation Cisco Integrated Services router (ISR G2). The original PoE EtherSwitch modules (ESW) on the 2800 and 3800 Integrated Services Routers (ISR) supported a 16 port (single wide) and a 36 port (dual wide) network module that supported Cisco proprietary power at up to 10 watts per port. These modules were replaced with IEEE 802.3af PoE modules that delivered power at up to 15.4 watts per port (16, 24, and 48 port varieties). Unfortunately, the ISR router power supplies did not have enough power to deliver power to the PoE ports and an external power chassis was normally required to be daisy chained off of the network modules. The 2900 ISR G2 router supports up to 2 power supplies (BOOST) for increase PoE delivery at up to 20 watts per port (Cisco enhanced Power over Ethernet – ePoE). The 2900 series router only supports one power supply, but can operate in boost mode by connecting the 2900 series router to a redundant power system (RPS 2300). The 3945 series router supports up to 65 phones using IEEE 802.3af inline power (15.4 watts) with 2 power supplies. The number of powered devices supported differs based on the amount of power required by the device and the ISR G2 router used to deliver PoE. Table 3 of the first link at the end of this blog details the number of devices supported in normal mode (single power supply) and boost mode (dual power supplies or 2900 + RPS 2300). Table 7 of the ESW link describes the maximum number of modules that can be used in different ISR G2 routers (2911, 2921, 2951, 3925, 3945). The new PoE service modules come in 16, 24, and 48 port varieties of Fast Ethernet or Gigabit Ethernet. Most of the Fast Ethernet PoE service modules have one Gigabit Ethernet uplink port. The 48 port Fast Ethernet PoE service module does not come with a Gigabit Ethernet uplink port. The service modules require Cisco IOS 15(0).1 on any of the ISR G2 routers. Link: Cisco Enhanced EtherSwitch Service Modules for Cisco 2900 and 3900 series routers. Cisco Redundant Power System 2300

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