# Gigabit Ethernet I/O Modules and IOAs

Gigabit Ethernet interfaces are supported on the following modules:

- GE I/O module
- GE-2 SFP I/O module
- GE-8 I/O module
- OC3-2 GE APS I/O module
- ES2-S1 GE-4 IOA
- ES2-S1 GE-8 IOA
- ES2-S3 GE-20 IOA

## GE I/O Module

ERX7xx models, ERX14xx models, and the ERX310 router all support the GE I/O module.

You can pair any of the following types of GE I/O modules with the GE/FE line module:

- The GE I/O SFP module uses a range of SFPs to support different optical modes and cabling distances. The I/O module accepts up to two pairs (Tx/Rx) of LC-style fiber-optic connectors that support different optical modes and cabling distances. Alternatively, the I/O module supports up to two pairs of copper SFPs.
- The GE I/O MULTI MODE module accepts up to two pairs (Tx/Rx) of SC-style fiber-optic connectors.
- The GE I/O SINGLE MODE module accepts up to two pairs (Tx/Rx) of SC-style fiber-optic connectors.

The GE I/O module has two ports: one port (port 0) is active (also known as primary), and the other port (port 0R) is redundant. If the active port fails, the redundant port automatically becomes active.

You can configure only port 0 for a Gigabit Ethernet interface; you cannot configure redundant port 0R. Cabling both ports provides a redundant path to the Gigabit Ethernet interface.

## GE-2 SFP I/O Module

The ERX1440 router and the ERX310 routers both support the GE-2 SFP I/O module. Other E Series routers do not support the GE-2 SFP I/O module. The GE-2 SFP I/O module was previously called the 2XGE APS I/O module.

The GE-2 SFP I/O module pairs with the GE-2 line module and the GE-HDE line module. You can install the GE-2 line module or the GE-HDE line module and its corresponding GE-2 SFP I/O module in slot 1 or slot 2 of an ERX310 router or in any slot of an ERX1440 router.

The GE-2 SFP I/O module can use either fiber-optic or copper SFPs. The I/O module accepts up to two pairs (Tx/Rx) of LC-style fiber-optic connectors that support different optical modes and cabling distances. Alternatively, the I/O module supports up to two pairs of copper SFPs.

### Ports on GE-2 SFP I/O Module

The GE-2 SFP I/O module has four ports: two ports (port 0 and port 1) are active (also known as primary), and the other two ports (port 0R and port 1R) are redundant. If an active port fails, its corresponding redundant port automatically becomes active.

You can configure only port 0 and port 1 for a Gigabit Ethernet interface; you cannot configure redundant ports 0R and 1R. Cabling an active port and its corresponding redundant port (that is, port 0 and port 0R, or port 1 and port 1R) provides a redundant path to the Gigabit Ethernet interface.

### Bandwidth and Line Rate Considerations

When the GE-2 line module or the GE-HDE line module is installed in the ERX1440 router, it delivers full bandwidth of 2 Gbps per port only when installed in slot 2 or slot 4, and when the SRP-40G+ module is used in the router. When the module is installed in any other ERX1440 slot, it delivers a maximum bandwidth of 2 Gbps per line module (1 Gbps maximum at the ingress and 1 Gbps maximum at the egress). Therefore, of the maximum 24 possible ports for the module in an ERX1440 chassis (that is, two ports in each of 12 slots), full bandwidth is delivered only on a maximum of four ports (those in slots 2 and 4).

When the GE-2 line module or the GE-HDE line module is installed in either the ERX1440 router or the ERX310 router and both ports are active, line rate performance is achieved only with packets that are 174 bytes or larger. The module might not achieve line rate with packets that are smaller than 174 bytes.

## GE-8 I/O Module

The ERX1440 and ERX310 routers both support the GE-8 I/O module. Other E Series routers do not support the GE-8 I/O module.

The GE-8 I/O module pairs with the GE-HDE line module to provide Gigabit Ethernet operation through eight line interfaces.

| Note: The GE-8 I/O module has a logical port, numbered port 8, that is reserved for the hardware multicast packet replication feature. For more information, see JunosE Multicast Routing Configuration Guide .

You can install the GE-HDE line module and its corresponding GE-8 I/O module in slot 1 or slot 2 of an ERX310 router or in any slot of an ERX1440 router.

The GE-8 I/O module can use either fiber-optic or copper SFPs. The I/O module accepts up to eight pairs (Tx/Rx) of LC-style fiber-optic connectors that support different optical modes and cabling distances. Alternatively, the I/O module supports up to eight pairs of copper SFPs.

### Bandwidth and Line Rate Considerations

When the GE-HDE line module is installed in the ERX1440 router, it delivers full bandwidth of 4 Gbps per line module (2 Gbps at the ingress and 2 Gbps at the egress) only when installed in slot 2 or slot 4, and when the SRP-40G+ module is used in the router. When the module is installed in any other ERX1440 slot, it delivers a maximum bandwidth of 2 Gbps per line module (1 Gbps maximum at the ingress and 1 Gbps maximum at the egress). Therefore, of the maximum 96 possible ports for the module in an ERX1440 chassis (that is, eight ports in each of 12 slots), full bandwidth is delivered only on a maximum of 16 ports (those in slots 2 and 4).

When the GE-HDE line module is installed in either the ERX1440 or the ERX310 router and all ports are active, line rate performance is achieved only with packets that are 174 bytes or larger. The module might not achieve line rate with packets that are smaller than 174 bytes.

Table 14 lists the average data rate on the GE-HDE line module and GE-8 I/O module combination when installed in an ERX310 router or in slots 2 or 4 of an ERX1440 router.

Table 14: Average Data Rate for ERX310 router or in Slots 2 or 4 of an ERX1440 router

Port Combination | Average Data Rate per GE-8 I/O Module (> 174 Byte Packets) | Average Data Rate per GE-HDE Line Module
--- | --- | ---
Ports 1–8 | 250 Mbps per port | 250 Mbps per port
Any four ports | 500 Mbps per port | 500 Mbps per port
Any two ports | 1 Gbps per port | 1 Gbps per port

Table 15 lists the average data rate on the GE-HDE line module and GE-8 I/O module combination when installed in all other slots on the ERX1440.

Table 15: Average Data Rate When Installed in All Other Slots on an ERX1440 router

Port Combination | Average Data Rate per GE-8 I/O Module (> 174 Byte Packets) | Average Data Rate per GE-HDE Line Module
--- | --- | ---
Ports 1–8 | 125 Mbps per port | 125 Mbps per port
Any four ports | 250 Mbps per port | 250 Mbps per port
Any two ports | 500 Mbps per port | 500 Mbps per port

### Managing High-Density Ethernet

The overall data rate for the GE-HDE line module is 2 Gbps; therefore, the I/O module becomes highly oversubscribed because of the wire rate of the line module. The data rate of the GE-8 I/O module is limited with larger frames, and the packet rate is limited with smaller frames.

Currently, flow control using MAC pause frames is disabled on the GE-8 I/O module. The I/O module does not transmit or receive pause frames.

For more information about high-density Ethernet, see High-Density Ethernet.

## OC3-2 GE APS I/O Module

ERX7xx models, ERX14xx models, and the ERX310 router all support the OC3-2 GE APS I/O module.

The OC3-2 GE APS I/O module pairs with the OC3/STM1 GE/FE line module to provide Gigabit Ethernet operation through one line interface and OC3 STM1 ATM operation through two line interfaces.

The OC3-2 GE APS I/O module uses a range of SFPs to support different optical modes and cabling distances, and accepts up to three LC-style fiber-optic or copper SFPs. You can configure only port 2 for Gigabit Ethernet interfaces; port 0 and port 1 are reserved for OC3/STM1 ATM interfaces.

For more information about configuring OC3/STM-1 ATM interfaces on this I/O module, see OC3/STM1 GE/FE Line Module.

| Note: The OC3-2 GE APS I/O module does not support APS in the current release.

## ES2-S1 GE-4 IOA

The E120 and E320 routers support the ES2-S1 GE-4 IOA. Other E Series routers do not support the ES2-S1 GE-4 IOA.

The ES2-S1 GE-4 IOA pairs with the ES2 4G line module (LM). For more information about the ES2 4G LM, see ES2 4G Line Module.

The ES2-S1 GE-4 IOA is offered in a halfheight size that enables you to configure it in one of two IOA bays that are available for each slot. You can install the ES2-S1 GE-4 IOA in only one of the IOA bays per slot.For more information about installing IOAs, see the E120 and E320 Hardware Guide.

The ES2-S1 GE-4 IOA has four ports. The IOA can use either fiber-optic or copper SFPs. The IOA accepts up to four pairs (Tx/Rx) of LC-style fiber-optic connectors that support different optical modes and cabling distances. Alternatively, the IOA supports up to eight pairs of copper SFPs.

The ES2-S1 GE-4 IOA does not support port redundancy.

## ES2-S1 GE-8 IOA

The E120 and E320 routers support the ES2-S1 GE-8 IOA. Other E Series routers do not support the ES2-S1 GE-8 IOA.

The ES2-S1 GE-8 IOA is offered in a halfheight size that enables you to configure it in either of the two IOA bays that are available for each slot. You can install the ES2-S1 GE-8 IOA in both IOA bays. For more information about installing IOAs, see the E120 and E320 Hardware Guide.

The ES2-S1 GE-8 IOA has eight ports. The IOA can use either fiber-optic or copper SFPs. The IOA accepts up to four pairs (Tx/Rx) of LC-style fiber-optic connectors that support different optical modes and cabling distances. Alternatively, the IOA supports up to eight pairs of copper SFPs.

| Note: The ES2-S1 GE-8 IOA has a logical port, numbered port 8, that is reserved for the hardware multicast packet replication feature. For more information, see JunosE Multicast Routing Configuration Guide .

The ES2-S1 GE-8 IOA pairs with either the ES2 4G line module (LM), ES2 10G LM, and the ES2 10G ADV LM to provide access services.

### ES2 4G LM Combination

For more information about the ES2 4G LM, see ES2 4G Line Module.

When paired with the ES2 4G LM, you can combine the ES2-S1 GE-8 IOA in a slot with one of the following IOA types:

- ES2-S1 OC3-8 ATM IOA
- ES2-S1 OC12-2 ATM IOA
- ES2-S1 OC12-2 POS IOA

#### Bandwidth and Line Rate Considerations

Table 16 lists the average data rate on the ES2-S1 GE-8 IOA when installed in E120 and E320 routers with one ES2 4G LM installed.

Table 16: Average Data Rate for One ES2-S1 GE-8 IOA Installed with an ES2 4G LM

Port Combination | 100 Gbps Configuration (E320 router) | 120 Gbps and 320 Gbps Configurations (E120 and E320 routers)
--- | --- | ---
Average Data Rate per GE-8 IOA (> 128 Byte Packets) | Average Data Rate per ES2 4G LM | Average Data Rate per GE-8 IOA (> 128 Byte Packets) | Average Data Rate per ES2 4G LM
All eight ports | 412.5 Mbps per port | 412.5 Mbps per port | 475 Mbps per port | 475 Mbps per port
Any four ports | 825 Mbps per port | 825 Mbps per port | 950 Mbps per port | 950 Mbps per port
Any two ports | 1 Gbps per port | 1 Gbps per port | 1 Gbps per port | 1 Gbps per port

Table 17 lists the average data rate on two ES2-S1 GE-8 IOAs when installed in E120 and E320 routers with one ES2 4G LM installed.

Table 17: Average Data Rate for Two ES2-S1 GE-8 IOAs Installed with an ES2 4G LM

Port Combination | 100 Gbps Configuration (E320 router) | 120 Gbps and 320 Gbps Configurations (E120 and E320 routers)
--- | --- | ---
Average Data Rate per GE-8 IOA (> 128 Byte Packets) | Average Data Rate per ES2 4G LM | Average Data Rate per GE-8 IOA (> 128 Byte Packets) | Average Data Rate per ES2 4G LM
All sixteen ports | 206.25 Mbps per port | 206.25 Mbps per port | 237.5 Mbps per port | 237.5 Mbps per port
Any eight ports | 412.5 Mbps per port | 412.5 Mbps per port | 475 Mbps per port | 475 Mbps per port
Any four ports | 825 Mbps per port | 825 Mbps per port | 950 Mbps per port | 950 Mbps per port
Any two ports | 1 Gbps per port | 1 Gbps per port | 1 Gbps per port | 1 Gbps per port

Table 18 lists the average data rate when combining an ES2-S1 GE-8 IOA in one adapter bay with the ES2-S1 OC3-8 ATM IOA, or the ES2-S1 OC12-2 ATM IOA, or the ES2-S1 OC12-2 POS IOA in another adapter bay. Because the OC3/STM1 and OC12/STM4 IOAs use less than half of the full bandwidth of the ES2 4G LM, the router allocates these IOAs as much bandwidth as they can use. The ES2-S1 GE-8 IOA uses any remaining bandwidth.

Each OC12/STM4 port has a maximum theoretical bandwidth of 622 Mbps. Each OC3/STM1 port has a maximum theoretical bandwidth of 155 Mbps. Therefore, the OC12/STM4 IOAs have a maximum theoretical bandwidth of 1.244 Gbps and the OC3/STM1 IOA has an maximum theoretical bandwidth of 1.244 Gbps.

Table 18: Average Data Rate for ES2-S1 GE-8 IOA Combined with Other IOA Types in Same Slot

Average Data Rate per GE-8 IOA (> 128 Byte Packets) | Average Data Rate per OC12/STM4 IOA | 100 Gbps Configuration (E320 router) Average Data Rate per ES2 4G LM | 120 Gbps and 320 Gbps Configurations (E120 and E320 routers) Average Data Rate per ES2 4G LM
--- | --- | --- | ---
257 Mbps per port (Ports 0–7) | 622 Mbps per port (Ports 0 and 1) | GE-8 IOA—257 Mbps per port OC12/STM4—622 Mbps per port | GE-8 IOA—319.5 Mbps per port OC12/STM4—622 Mbps per port
334.75 Mbps per port (Ports 0–7) | 622 Mbps (Port 1) | GE-8 IOA—334.75 Mbps per port OC12/STM4 IOA—622 Mbps for port 1 | GE-8 IOA—397.25 Mbps per port OC12/STM4 IOA—622 Mbps for port 1
387.5 Mbps per port (Ports 0–7) | 100 Mbps per port (Ports 0 and 1) | GE-8 IOA—387.5 Mbps per port OC12/STM4 IOA—100 Mbps per port | GE-8 IOA—450 Mbps per port OC12/STM4 IOA—100 Mbps per port

#### Managing High-Density Ethernet

With a 100 Gbps fabric configuration, the overall data rate for the ES2 4G LM with ES2-S1 GE-8 IOAs is 3.3 Gbps. With a 120 Gbps fabric configuration or a 320 Gbps fabric configuration, the overall data rate for the ES2 4G LM with ES2-S1 GE-8 IOAs is 3.8 Gbps. In both configurations, the line module becomes highly oversubscribed because of the IOA available wire rate. When paired with the ES2 4G LM, the data rate of the ES2-S1 GE-8 IOA is bandwidth limited with larger frames, and the packet rate is limited with smaller frames.

| Note: The overall data rate of the ES2-S1 GE-8 IOA is 0.1 Gbps less than other IOAs that pair with the ES2 4G LM because of fair bandwidth allocation across the eight ports.

Currently, flow control using MAC pause frames is disabled on the ES2-S1 GE-8 IOA. The IOA does not transmit or receive pause frames.

For more information about high-density Ethernet on E Series routers, see High-Density Ethernet.

### ES2 10G LM Combination

When paired with the ES2 10G LM, you can only combine the ES2-S1 GE-8 IOA in a slot with another ES2-S1 GE-8 IOA.

With a 100 Gbps fabric configuration, the E320 router can accommodate up to 2 combinations of ES2 10G LMs and ES2-S1 GE-8 IOAs. You must install a combination in either of the turbo slots (slot 2 or slot 4). The 100 Gbps allocates 10 Gbps of overall bandwidth to each of these slots.

With a 120 Gbps fabric configuration, the E120 router can accommodate up to 6 combinations of ES2 10G LMs and ES2-S1 GE-8 IOAs. You can install a combination in any of the line module slots, each of which is allocated 10 Gbps of overall bandwidth.

With a 320 Gbps fabric configuration, the E320 router can accommodate up to 12 combinations of ES2 10G LMs and ES2-S1 GE-8 IOAs. You can install a combination in any of the line module slots, each of which is allocated 10 Gbps of overall bandwidth.

#### Bandwidth and Line Rate Considerations

Each ES2-S1 GE-8 IOA is connected to the ES2 10G LM through a 5 Gbps bus. Therefore, the aggregate bandwidth of any IOA is limited to 5 Gbps.

Table 19 lists the average data rate on the ES2-S1 GE-8 IOA when installed in E120 and E320 routers with one ES2 10G LM installed.

Table 19: Average Data Rate for One ES2-S1 GE-8 IOA Installed with an ES2 10G LM

Port Combination | 100 Gbps, 120 Gbps, or 320 Gbps Configuration Average Data Rate per GE-8 IOA (> 128 Byte Packets)
--- | ---
Any five ports | 1 Gbps per port
All eight ports | 625 Mbps per port

Table 20 lists the average data rate of two ES2-S1 GE-8 IOAs when installed in E120 and E320 routers with one ES2 10G LM installed.

Table 20: Average Data Rate for Two ES2-S1 GE-8 IOAs Installed with an ES2 10G LM

Port Combination | 100 Gbps, 120 Gbps, or 320 Gbps Configuration Average Data Rate per GE-8 IOA (> 128 Byte Packets)
--- | ---
All sixteen ports | 625 Mbps per port
Any five ports on each IOA | 1 Gbps per port

#### Managing High-Density Ethernet

When installed in an E120 or an E320 router with any SRP module combination, the overall data rate for the ES2 10G LM with one ES2-S1 GE-8 IOA is limited to 5 Gbps. The overall data rate for the ES2 10G LM with two ES2-S1 GE-8 IOAs is limited to 10 Gbps. In all configurations, the line module can become oversubscribed because of the IOA available wire rate (8 Gbps).

Currently, flow control using MAC pause frames is disabled on the ES2-S1 GE-8 IOA. The IOA does not transmit or receive pause frames.

For more information about high-density Ethernet on E Series routers, see High-Density Ethernet.

### ES2 10G ADV LM Combination

You can combine an ES2–S1 GE-8 IOA in a slot only with another ES2–S1 GE-8 IOA when paired with the ES2 10G ADV LM.

With a 120 Gbps fabric configuration, the E120 router can accommodate up to 6 combinations of ES2 10G ADV LMs and ES2-S1 GE-8 IOAs. You can install a combination in any of the line module slots, each of which is allocated 10 Gbps of overall bandwidth.

With a 320 Gbps fabric configuration, the E320 router can accommodate up to 12 combinations of ES2 10G ADV LMs and ES2-S1 GE-8 IOAs. You can install a combination in any of the line module slots, each of which is allocated 10 Gbps of overall bandwidth.

#### Bandwidth and Line Rate Considerations

Each ES2-S1 GE-8 IOA is connected to the ES2 10G ADV LM through a 5 Gbps bus. Therefore, the aggregate bandwidth of any IOA is limited to 5 Gbps.

Table 21 lists the average data rate on the ES2-S1 GE-8 IOA when installed in E120 and E320 routers with one ES2 10G ADV LM installed.

Table 21: Average Data Rate for One ES2-S1 GE-8 IOA Installed with an ES2 10G ADV LM

Port Combination | 100 Gbps, 120 Gbps, or 320 Gbps Configuration Average Data Rate per GE-8 IOA (> 128 Byte Packets)
--- | ---
Any five ports | 1 Gbps per port
All eight ports | 625 Mbps per port

Table 22 lists the average data rate of two ES2-S1 GE-8 IOAs when installed in E120 and E320 routers with one ES2 10G ADV LM installed.

Table 22: Average Data Rate for Two ES2-S1 GE-8 IOAs Installed with an ES2 10G ADV LM

Port Combination | 100 Gbps, 120 Gbps, or 320 Gbps Configuration Average Data Rate per GE-8 IOA (> 128 Byte Packets)
--- | ---
All sixteen ports | 625 Mbps per port
Any five ports on each IOA | 1 Gbps per port

#### Managing High-Density Ethernet

When installed in an E120 or E320 router with any SRP module combination, the overall data rate for the ES2 10G ADV LM with one ES2-S1 GE-8 IOA is limited to 5 Gbps. The overall data rate for the ES2 10G ADV LM with two ES2-S1 GE-8 IOAs is limited to 10 Gbps. In all configurations, the line module can become oversubscribed because of the IOA available wire rate (8 Gbps).

Currently, flow control using MAC pause frames is disabled on the ES2-S1 GE-8 IOA. The IOA does not transmit or receive pause frames.

For more information about high-density Ethernet on E Series routers, see High-Density Ethernet.

## ES2-S3 GE-20 IOA

The E120 and E320 routers support the ES2-S3 GE-20 IOA. Other E Series routers do not support the ES2-S3 GE-20 IOA.

The ES2-S3 GE-20 IOA pairs with the ES2 10G LM or the ES2 10G ADV LM to provide Gigabit Ethernet operation through 20 line interfaces.

The ES2-S3 GE-20 IOA is offered in a full-height size that uses both adapter bays. The IOA is identified by the software as adapter bay 0. For more information about installing IOAs, see the E120 and E320 Hardware Guide.

The IOA can use either fiber-optic or copper SFPs. The IOA accepts up to four pairs (Tx/Rx) of LC-style fiber-optic connectors that support different optical modes and cabling distances.

The ES2-S3 GE-20 IOA does not support port redundancy.

### ES2 10G LM Combination

With a 100 Gbps fabric configuration, the E320 router can accommodate up to 2 combinations of ES2 10G LMs and ES2-S3 GE-20 IOAs. You must install a combination in either of the turbo slots (slot 2 or slot 4). The 100 Gbps allocates 10 Gbps of overall bandwidth to each of these slots.

With a 120 Gbps fabric configuration, the E120 router can accommodate up to 6 combinations of ES2 10G LMs and ES2-S3 GE-20 IOAs. You can install a combination in any of the line module slots, each of which is allocated 10 Gbps of overall bandwidth.

With a 320 Gbps fabric configuration, the E320 router can accommodate up to 12 combinations of ES2 10G LMs and ES2-S3 GE-20 IOAs. You can install a combination in any of the line module slots, each of which is allocated 10 Gbps of overall bandwidth.

### Bandwidth and Line Rate Considerations

Table 23 lists the average data rate on the ES2-S3 GE-20 IOA when installed in E120 and E320 routers with one ES2 10G LM installed.

Table 23: Average Data Rate for One ES2-S3 GE-20 IOA Installed with an ES2 10G LM

Port Combination | 100 Gbps, 120 Gbps, or 320 Gbps Configuration Average Data Rate per GE-20 IOA (> 128 Byte Packets)
--- | ---
Any 10 ports | 1 Gbps per port
All 20 ports | 500 Mbps per port

### Managing High-Density Ethernet

When installed in an E120 or E320 router with any SRP module combination, the overall data rate for the ES2 10G LM with one ES2-S3 GE-20 IOA is limited to 10 Gbps. The line module can become oversubscribed because of the IOA available wire rate (20 Gbps).

Currently, flow control using MAC pause frames is disabled on the ES2-S3 GE-20 IOA. The IOA does not transmit or receive pause frames.

For more information about high-density Ethernet on E Series routers, see High-Density Ethernet .

### ES2 10G ADV LM Combination

With a 100 Gbps fabric configuration, the E320 router can accommodate up to 2 combinations of ES2 10G ADV LMs and ES2-S3 GE-20 IOAs. You must install a combination in either of the turbo slots (slot 2 or slot 4). The 100 Gbps allocates 10 Gbps of overall bandwidth to each of these slots.

With a 120 Gbps fabric configuration, the E120 router can accommodate up to 6 combinations of ES2 10G ADV LMs and ES2-S3 GE-20 IOAs. You can install a combination in any of the line module slots, each of which is allocated 10 Gbps of overall bandwidth.

With a 320 Gbps fabric configuration, the E320 router can accommodate up to 12 combinations of ES2 ADV LMs and ES2-S3 GE-20 IOAs. You can install a combination in any of the line module slots, each of which is allocated 10 Gbps of overall bandwidth.

### Bandwidth and Line Rate Considerations

Table 24 lists the average data rate on the ES2-S3 GE-20 IOA when installed in E120 and E320 routers with one ES2 10G ADV LM installed.

Table 24: Average Data Rate for One ES2-S3 GE-20 IOA Installed with an ES2 10G ADV LM

Port Combination | 100 Gbps, 120 Gbps, or 320 Gbps Configuration Average Data Rate per GE-20 IOA (> 128 Byte Packets)
--- | ---
Any 10 ports | 1 Gbps per port
All 20 ports | 500 Mbps per port

### Managing High-Density Ethernet

When installed in an E120 or E320 router with any SRP module combination, the overall data rate for the ES2 10G ADV LM with one ES2-S3 GE-20 IOA is limited to 10 Gbps. The line module can become oversubscribed because of the IOA available wire rate (20 Gbps).

Currently, flow control using MAC pause frames is disabled on the ES2-S3 GE-20 IOA. The IOA does not transmit or receive pause frames.

For more information about high-density Ethernet on E Series routers, see High-Density Ethernet.