Cisco NCS 4216 Manual 

The Cisco NCS 4216 is a seven-rack unit router that belongs to the Cisco NCS 4200 family of routers. This router complements Cisco’s offerings for IP RAN solutions for the GSM, UMTS, LTE, and CDMA. Given its form-factor, interface types and GigabitEthernet density the Cisco NCS 4216 can also be positioned as a Carrier Ethernet aggregation platform. The Cisco NCS 4216 is a cost optimized, fully redundant, centralized forwarding, extended temperature, and flexible pre-aggregation router. • Cisco NCS 4216 Features, page 1 • Interface Numbering, page 22 • Regulatory Compliance, page 22 Cisco NCS 4216 Features The key feature of the Cisco NCS 4216 is to increase per platform and rack-unit interface density, especially when combining multiple interface types such as Gigabit Ethernet (GE), TDM, 10GE, 40GE and 100GE. The Cisco NCS 4216 has the following hardware features: • A large service scale and high throughput (400G) Route Switch Processors (RSP)—NCS4216-RSP • One-port 100GE Interface Module (NCS4200-1H-PK) • Two-port 40GE Interface Module (NCS4200-2Q-P) • Eight-port 10 Gigabit Ethernet Interface Module (8X10GE) (NCS4200-8T-PS) • SFP Combo IM—Eight-port Gigabit Ethernet (8X1GE) + One-port 10 Gigabit Ethernet (1X10GE) (NCS4200-1T8LR-PS) • OC-192 Interface Module with 8-port Low Rate CEM Interface Module (10G HO / 10G LO) (NCS4200-1T8S-10CS) • 48 T1/E1 TDM Interface Module (48XT1/E1) (NCS4200-48T1E1-CE) • 48 T3/E3 TDM Interface Module (48XT3/E3) (NCS4200-48T3E3-CE) • 900 Watt PSUs to power the new RSP modules Cisco NCS 4216 Hardware Installation Guide 1

• Chassis —Seven rack unit in height while still maintaining a shallow depth and side-to-side air flow. • Fan-tray with removable dust filter. • New form factor and high performance RSP—This high performance RSP has aggregate switching capacity of 480 Gbps in oversubscribed mode. • The backplane and the RSP together have the provision to support higher density 10GE modules like 8x10GE and 100GE modules. • Air flow baffle to allow a system to redirect air and allow front-to-back airflow for cooling. • Flexible I/O configurations through 16 hot pluggable interface modules (single width). For example, with NCS4216-RSP in oversubscribed mode: ◦16x10G + 2x100G + 80x1G ◦48x10G ◦48 T1/E1 TDM Interface Module (48XT1/E1) ◦48 T3/E3 TDM Interface Module (48XT3/E3) ◦OC-192 Interface Module with 8-port Low Rate CEM Interface Module (10G HO / 10G LO) • Metro ENET switching features along with TDM pseudo-wire support. • Network processor provides flexibility to off-load control plane CPU processing for select OAM and management packets (for example, CCM, BFD, LBM). • Flexible ENET processing through table-driven packet processing engines. • On-line insertion/removal (OIR) of all FRUs except GPS module, while the system is operational • Power supply (2+1)—Support for DC power supply. Two PSUs should be powered-on at a time. If all the three PSUs are powered on, they work in a load-sharing mode. • Fully-redundant system with redundant combined control plane and data plane (excluding interfaces), timing support, power supplies, and fans. • Active and standby support of redundant control plane and data plane, and timing • Intra-chassis IOS redundancy (requires both RSPs) • Stateful-switchover between active and standby RSPs (for protocols supported by IOS). • In-service software upgrade (ISSU) supported with same RSPs. • Timing support for receipt and distribution of network frequency and time including SyncE, BITS, 1PPS/10MHz I/O, IEEE 1588-2008, and NTP. • Support for ENET OAM. • T1/E1 and T3/E3 line protection compliant with NEBS GR-1089. • Patch Panel for the Interface Modules Cisco NCS 4216 Hardware Installation Guide 2 Cisco NCS 4216 Overview Cisco NCS 4216 Features

Figure 1: Cisco NCS 4216 Chassis Design Redundant power units (three DC power units are shown) 2 Mounting Bracket 1 Fan tray filter 4 Fan tray 3 RSP Slot 1 6 RSP Slot 0 5 Slot 0 for Interface Module 8 IM Carrier plates 7 Slot 2 for Interface Module 10 Slot 1 for Interface Module 9 Slot 4 for Interface Module 12 Slot 3 for Interface Module 11 Slot 6 for Interface Module 14 Slot 5 for Interface Module 13 Slot 8 for Interface Module 16 Slot 7 for Interface Module 15 Slot 10 for Interface Module 18 Slot 9 for Interface Module 17 Cisco NCS 4216 Hardware Installation Guide 3 Cisco NCS 4216 Overview Cisco NCS 4216 Features

Module 20 Slot 11 for Interface Module 19 Slot 14 for Interface Module 22 Slot 13 for Interface Module 21 Slot 15 for Interface Module 23 System Specifications The following table summarizes the system specifications and environmental requirements for the Cisco NCS 4216. Table 1: Cisco NCS 4216 System Specifications 12.224 inches x 17.426 inches x 9.33 inches Dimensions (Height x Width x Depth) 12.224 inches x 17.426 inches x 10.705 inches The additional depth is due to the projection of the handle from Chassis face. Note Dimensions with FRUs Weight 15.868 kg Chassis with back-plane 3.618 kg Fan tray 0.924 kg 900W DC PSU 2.8 kg RSP (NCS4216-RSP) The Cisco NCS 4216 supports the following temperature ranges at 1800 m operating altitude: • -40º C to 65º C with side-to-side air flow • -40º C to 55º C with front to back air flow Refer to Datasheets for system configuration. Note Operating Temperature -40º F to 158º F (-40º C to +70º C) storage temperature Nonoperating Temperature 5–95% operating non-condensing relative humidity Operating Humidity -60 m to 1800 m operating altitude for full operating temperature range; up to 4000 m at up to 40º C. Operating Altitude -60 m to 4570 m storage altitude Nonoperating Altitude Cisco NCS 4216 Hardware Installation Guide 4 Cisco NCS 4216 Overview System Specifications

Vibration 30 G half sine 6 ms and 11 ms Shock Random: 1.15 g RMS 3 to 200 Hz, 30 minutes/axis Sine: 10 to 500 Hz at 0.8 G peak / 5 sweep cycles/axis Nonoperating Vibration < 76 dBA at 27ºC as per NEBS standard GR-63 Operating Acoustics GNSS Module (NCS4216-CM-GNSS) The GNSS module is present on the RSP. It is a pluggable module that allows direct interface with the external antenna. Using a single GPS antenna input for both RSPs requires usage of external splitters. Note To reduce the risk of fire, use only No. 26 AWG or larger telecommunication line cord. Statement 1023 Warning The GNSS module is not hot swappable. Note GNSS Module RF Input Requirements • The GNSS module requires an active GPS/GNSS antenna with built-in Low-Noise Amplifier (LNA) for optimal performance. The antenna LNA amplifies the received satellite signals for two purposes: ◦Compensation of losses on the cable ◦Lifting the signal amplitude in the suitable range for the receiver frontend The Amplification required is 22dB gain + cable/connector loss + Splitter signal loss. The recommended range of LNA gain (LNA gain minus all cable and connector losses) at the connector of the receiver module is 22dB to 30dB with a minimum of 20dB and a maximum of 35dB. • GNSS module provides 5V to the active antenna through the same RF input. • Surge requirement: GNSS modules have built-in ESD protections on all pins, including the RF-input pin. However, additional surge protection may be required if rooftop antennas are being connected, to meet the regulations and standards for lightning protection in the countries where the end-product is installed. Cisco NCS 4216 Hardware Installation Guide 5 Cisco NCS 4216 Overview GNSS Module (NCS4216-CM-GNSS)

lightning protection must be capable of conducting all potentially dangerous electrical energy to PE (Protective Earth). Surge arrestors should support DC-pass and suitable for the GPS frequency range (1.575GHz) with low attenuation. • Antenna Sky visibility: GPS signals can only be received on a direct line of sight between antenna and satellite. The antenna should see as much as possible from the total sky. For proper timing, minimum of four satellites should be locked. The antenna terminal should be earthed at the building entrance in accordance with the ANSI/NFPA 70, the National Electrical Code (NEC), in particular Section 820.93, Grounding of Outer Conductive Shield of a Coaxial Cable. Note Power Supply Features The Cisco NCS 4216 supports DC power supplies. The DC power supplies support: • -40 VDC to -72 VDC The power supplies are hot-swappable. They are enclosed to prevent exposure to high voltages, and therefore, no power cable interlock is required. However, the power supplies are automatically shut down when removed from the chassis. The power supplies are rated to deliver 900W (~75A at +12VDC) to the other FRUs in the system. The DC power supply has dual input feeds. The following table shows the DC power supply specifications. Table 2: DC Power Supply Specifications A900-PWR900-D2 Part numbers 48V, GND, -48V Input power specification -40.0 V Minimum input voltage -72 VDC Maximum input voltage +12 VDC Output voltage 10 AWG minimum for -48/-60 VDC. Connector accepts 6AWG maximum. Wire gauge for DC input power connections 900 W Maximum power output For more information about installing the Cisco NCS 4216 power supplies, see the Installing the Power Supply. Cisco NCS 4216 Hardware Installation Guide 6 Cisco NCS 4216 Overview Power Supply Features

the normal operation of the chassis, at least two power supplies should be powered on. When all the three power supplies are plugged in, they work in a current sharing mode. Each power supply has dual feed. It is recommended to connect each power feed to a separate input source. Dying Gasp The Cisco NCS 4216 DC power supply does not support the Dying Gasp feature. Status LEDs LEDs are also provided on each power supply to indicate the status of the input power and the health of the power supply. For more information about the LEDs on the Cisco NCS 4216, see Troubleshooting section. The DC Power Supply Specifications table summarizes the input power specifications for the Cisco NCS 4216 DC power supply units. Fan Tray The fan tray modules supported on the router is: • ASR907-FAN-E The NCS4216 Fan tray uses • Four dual rotor fans—for the PSU area cooling • 12 fans (three columns for four fans)—60x60x38mm fans for the RSP and IM area The fan tray has the following hardware features: • It provides side-to-side forced air cooling • It provides redundant fans • It is field replaceable • It contains status LEDs For more information about air flow guidelines, see Air Flow Guidelines section. For instructions on how to install the fan tray, see Installing the Fan Tray section. For a summary of the LEDs on the fan tray, see LED Summary section. Dust Filter (A907-F2B-AIR) The dust filter on the fan tray is a quadrafoam 45PPI filter which is 85 percent dust resistant. For installing the fan filter, see Removing and Replacing the Dust Filter section. Cisco NCS 4216 Hardware Installation Guide 7 Cisco NCS 4216 Overview Fan Tray

Air Plenum or air baffle assembly is used change the air flow pattern of the unit. When the router is installed with the plenum, the air flow pattern is changed from side-side to front-back. The air flow front-back pattern provides a rack installation bay with a cool front zone and hot rear zone. For installing the plenum, see Installing the Air Plenum (A907-F2B-AIR) in the Rack section. When the air plenum and the fan filter are installed in the chassis, the system operating temperature is 55º C. Note Door The door provides access to the shelf, and acts as a protective panel. Front Door The front door of NCS 4216 provides access to the shelf, and fan-tray assembly. The front door acts as protective panels. The laser warning label is placed on the rear of the chassis. Cisco NCS 4216 Hardware Installation Guide 8 Cisco NCS 4216 Overview Fan Tray

Figure 2: Door Design RSP Modules The Cisco NCS 4216 is designed to use up to two RSP modules to handle the data plane, network timing, and control plane functionalities for the router. The RSP configuration allows you to use Cisco IOS software to control chassis management, redundancy, external management, and system status indications on the router. The following sections describe the Cisco NCS 4216 RSP: • Supported RSP Features • RSP Redundancy • Network Timing Interfaces • RSP Interfaces RSP features include: • Loading software onto processor-based interface modules Cisco NCS 4216 Hardware Installation Guide 9 Cisco NCS 4216 Overview RSP Modules

information, role negotiation, function for detection, health and status exchange, role negotiation • Packet processing • Traffic management, including buffering, queuing, and scheduling, Ethernet MAC functions • Network clocking functions including phase and time-of-day for BITS, 1 PPS, 10 MHz, and 1588 PTP clock references • Storage of software images, system configuration, SysLog • PTP packet processing including IEEE 1588-2008 for recovering network timing (frequency, phase, and time) from upstream PTP clocks, for generating PTP frequency and phase references as inputs to the SETS, and for distributing them to downstream PTP clocks • External management interfaces (RS232 console, management ENET, USB console, USB storage) and system status LED indicators Supported RSPs Effective Cisco IOS-XE Release 3.18.06v.S, the Cisco NCS 4216 supports the following RSP: • NCS4216-RSP—Provides 8 GB of SDRAM, 20 Mb of TCAM memory on every ASIC. The RSP does not provide external network interfaces for user traffic. All network interfaces are provided through separate IMs. Supported RSP Features The RSP provides the following features on the Cisco router: • Centralized data plane, timing, and control plane functions for the system • High-level control of interface modules • Management functionalities for the router • Control plane (host) CPU and associated memory in which Cisco IOS XE software and platform control software runs • Nonvolatile memory for storage of software images, configurations, and system files • Enabling and monitoring the health and presence of fan trays, interface modules, and power supplies • Field replacement and hot-swap capabilities Swapping of Interface Modules The following Ethernet interface modules support swapping on the Cisco NCS4216-RSP module: • SFP Combo IM—8-port Gigabit Ethernet (8X1GE) + 1-port 10 Gigabit Ethernet (1X10GE) • 2-port 40 Gigabit Ethernet Interface Module (2X40GE) • 1-port 10 Gigabit Ethernet (1 X SFP+) / 1-port Gigabit Ethernet (1 X SFP) / 2-port Gigabit Ethernet (1 X CSFP) and 16-port Gigabit Ethernet (8 X CSFP) / 8-port Gigabit Ethernet (8 X SFP) Interface Module Cisco NCS 4216 Hardware Installation Guide 10 Cisco NCS 4216 Overview RSP Modules

• 1-port 100 Gigabit Ethernet Interface Module (1X100GE) • OC-192 Interface Module with 8-port Low Rate CEM Interface Module (10G HO / 10G LO) • 48 T1/E1 TDM Interface Module (48XT1/E1) • 48 T3/E3 TDM Interface Module (48XT3/E3) Use the hw-module subslot default command before performing a swap of the modules to default the interfaces on the interface module. See the Cisco NCS 4216 Router Hardware Installation Guide for information on Supported Interface Modules on the RSP. Table 3: NCS4216-RSP Supported Interface Modules and Part Numbers Slot Part Number Interface Modules RSP Module 2,5,6,9,10,13,14,15 SFP Combo IM—8-port Gigabit NCS4200-1T8LR-PS Ethernet (8X1GE) + 1-port 10 Gigabit Ethernet (1X10GE) NCS4216-RSP 7,8 NCS4200-1H-PK 1x100G Interface module 3,4,7,8,11,12 NCS4200-2Q-P 2x40G Interface module 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14 and 15 1 1-port 10 Gigabit Ethernet (1 X NCS4200-1T16G-PS SFP+) / 1-port Gigabit Ethernet (1 X SFP) / 2-port Gigabit Ethernet (1 X CSFP) and 16-port Gigabit Ethernet (8 X CSFP) / 8-port Gigabit Ethernet (8 X SFP) Interface Module 3,4,7,8,11,12 NCS4200-8T-PS 8x10G Interface module 3,4,7,8,11,12 OC-192 Interface Module with NCS4200-1T8S-10CS 8-port Low Rate CEM Interface Module (10G HO / 10G LO) 0,1,2,3,4,5,6,7,8,9,10,13,14,15 NCS4200-48T1E1-CE 48XT1/E1 Interface module 0,1,2,3,4,5,6,7,8,9,10,13,14,15 NCS4200-48T3E3-CE 48XT3/E3 Interface module 1 Only limited support to slots 0,1,2,5,6,9,10,11,12,13,14 and 15. There are slot specific restrictions to use NCS4200-1T16G-PS interface modules (IMs) with other IMs in the chassis. Contact Cisco Sales/Support for the valid combinations. Cisco NCS 4216 Hardware Installation Guide 11 Cisco NCS 4216 Overview RSP Modules

redundant RSPs, one RSP operates in the active mode and the other operates in the hot standby mode. Removal or failure of the active RSP results in an automatic switchover to the standby RSP. Interface Module Slot support will vary based on Interface Modules used in other slots. For more information, refer the Configuration Guides for details. Note Network Timing Interfaces The RSP supports the following network timing interfaces: • BITS input/output port—RJ48 jack • Wire Wrap Interface Through an Adapter • 1 PPS input and output—Mini coax connectors • 2.048 or 10 MHz input and output—Mini coax connectors • Time of Day (ToD) or 1 PPS input or output port—Shielded RJ45 jack Network timing interfaces support redundancy in a redundant RSP configuration. Network timing interfaces on a redundant RSP remain in operation while the RSP is in hot standby mode. RSP Interfaces The following figure summarizes the interfaces on the RSP module. Figure 3: Interfaces on the RSP Module Interface Label 1 PPS input timing port 1 1 PPS output timing port 2 10 MHz input timing port 3 10 MHz output timing port 4 Cisco NCS 4216 Hardware Installation Guide 12 Cisco NCS 4216 Overview RSP Modules

5 USB console port 6 USB memory port 7 Ethernet management port 8 BITS timing port 9 Interface Modules The network interfaces are provided through pluggable interface modules. The following list describes the various IM port density: • GE SFP ports—Supports 100/1000 modes • GE C-SFP ports—Supports 100/1000BASE-BX modes • 100GE CPAK ports using 1x100G IM • 10GE ports through SFP+ • 2X40 GE interface module—Supports QSFP mode • T1/E1 ports with integrated inter-office surge protection—Supports TDM channelized, PWE3 processing • T3/E3 ports - Supports TDM channelized, PWE3 Processing • OC3/OC12/OC48/OC192 - Supports TDM channelized, PWE3 Processing For information about supported interface modules, see the data sheet for the Cisco NCS 4200 Series Aggregation Services Routers. Note The Cisco NCS 4216 interface modules are a field-replaceable units. In addition to the ports provided on an RSP, the Cisco NCS 4216 supports the interface modules. Cisco NCS 4216 Hardware Installation Guide 13 Cisco NCS 4216 Overview Interface Modules

Figure 4: 8x10 Gigabit Ethernet Interface Module The high density 8x10 Gigabit Ethernet interface module supports eight 10 Gigabit Ethernet ports using SFP+ transceivers cages on the faceplate. It does not support XFP transceivers on the ports. Note For more information about installing a 8X10GE module, see the Interface Module Installation section. Cisco NCS 4216 Hardware Installation Guide 14 Cisco NCS 4216 Overview Interface Modules

Figure 5: 1x100 Gigabit Ethernet Interface Module The single port 100 Gigabit Ethernet interface module supports100 Gigabit Ethernet port. The figure above shows the interface module. For more information about installing a 1X100GE module, see the Interface Module Installation section. Cisco NCS 4216 Hardware Installation Guide 15 Cisco NCS 4216 Overview Interface Modules

Figure 6: 8x1 GE SFP+ 1x10 GE SFP Interface Module The 8-port 1 Gigabit Ethernet SFP interface module with the 1-port 10 Gigabit Ethernet interface module is a high density combination interface module. This module supports 8 Gigabit Ethernet SFP ports and 1 10 Gigabit Ethernet SFP+ port. For more information about installing the 8X1 GE SFP + 1X10 SFP Gigabit Ethernet module, see the Interface Module Installation section. Cisco NCS 4216 Hardware Installation Guide 16 Cisco NCS 4216 Overview Interface Modules

Figure 7: 2x40 Gigabit Ethernet Interface Module The dual port 40 Gigabit Ethernet interface module supports the 40 Gigabit Ethernet port. The 40G interface is supported using QSFP+ optics. The figure above shows the interface module. For more information about installing a 2X40 GE module, see the Interface Module Installation section. 1-port 10 Gigabit Ethernet (1 X SFP+) / 1-port Gigabit Ethernet (1 X SFP) / 2-port Gigabit Ethernet (1 X CSFP) and 16-port Gigabit Ethernet (8 X CSFP) / 8-port Gigabit Ethernet (8 X SFP) Interface Module The NCS4200-1T16G-PS interface module has the flexibility to support SFP+/SFP/CSFP on the modules as mentioned below: • 1-Port 10 Gigabit Ethernet Small Form-Factor Pluggable (SFP+) interface supports one of three modules as 1xSFP+, 1xSFP or 1xCSFP. Cisco NCS 4216 Hardware Installation Guide 17 Cisco NCS 4216 Overview Interface Modules

8xCSFP. Figure 8: NCS4200-1T16G-PS Gigabit Ethernet Interface Module For more information about installing a 1xSFP or CSFP and 8xSFP or CSFP, see Installing an Interface Module. For more information on port numbering, see Configuring 1-port 10 Gigabit Ethernet (1 X SFP+) / 1-port Gigabit Ethernet (1 X SFP) / 2-port Gigabit Ethernet (1 X CSFP) and 16-port Gigabit Ethernet (8 X CSFP) / 8-port Gigabit Ethernet (8 X SFP) Interface Module chapter of the Cisco NCS 4200 Series Software Configuration Guide, Cisco IOS XE Everest 16.6.1. Cisco NCS 4216 Hardware Installation Guide 18 Cisco NCS 4216 Overview Interface Modules

The OC-192 interface module with 8-port low rate CEM interface module is a high density combination interface module. This module supports 1 OC-192 port and 8 low rate CEM or 1 Gigabit Ethernet port. Figure 9: OC-192 Interface Module For more information about installing the OC-192 interface module, see the Interface Module Installation section. 48 X T1/E1 CEM Interface Module The 48 X T1/E1 interface module provides connectivity for up to 48 x T1/E1 ports through 3 high-density connectors on the front panel. Each port supports 16 TX and RX ports. For information on LEDs, see the Troubleshooting section. Figure 10: 48 x T1/E1 Interface Module Cisco NCS 4216 Hardware Installation Guide 19 Cisco NCS 4216 Overview Interface Modules

section. 48 X T3/E3 CEM Interface Module The 48 X T3/E3 interface module provides connectivity for up to 48 x T3/E3 ports through 3 high-density connectors on the front panel. Each port supports 16 TX and RX ports. For information on LEDs, see the Troubleshooting section. Figure 11: 48 x T3/E3 Interface Module For more information about installing the 48 X T3/E3 interface module, see the Interface Module Installation section. Temperature Sensor The Cisco NCS 4216 has a temperature sensor to detect ambient overtemperature conditions inside the chassis. The operating temperature range is between –40 C to +65 C. Temperatures outside this range are reported to the processor as an interrupt, and the software takes action to generate the appropriate alarms. Patch Panel The Cisco NCS 4216 has patch panel modules that provide interconnections with the interface modules. The following table shows three different types of patch panel: Table 4: Types of Patch Panel Description Patch Panel 48X75 ohm E1/DS1 termination, through DIN 1.0/2.3 connectors PANEL-48-1-DIN Cisco NCS 4216 Hardware Installation Guide 20 Cisco NCS 4216 Overview Temperature Sensor

connector PANEL-48-1-RJ48 48X75 ohm E3/DS3 termination, through DIN 1.0/2.3 connectors PANEL-48-3-DIN The interface modules, 48 T1/E1 TDM Interface Module (48XT1/E1) and 48 T3/E3 TDM Interface Module (48XT3/E3) can support a maximum of 48 TDM ports. These ports are available on the interface module through three Very-High-Density Cable Interconnect (VHDCI) connectors. The patch panels listed above make these 48 ports available to the customer. Figure 12: Patch Panel Line Interface View Figure 13: Patch Panel System Interface View Figure 14: Patch Panel Rear View Cisco NCS 4216 Hardware Installation Guide 21 Cisco NCS 4216 Overview Patch Panel

• The numbering format is Interface type slot or interface number. Interface (port) numbers begin at logical 0 for each interface type. • Interface module slots are numbered from bottom to top, with logical interfaces on each module numbered from left to right. Interfaces are hard-wired. Therefore, port 0 is always logical interface 0/0, port 1 is always logical interface 0/1, and so on. The following commands display the active RP slot number. The interface module is referenced as 1/x instead of 0/x: • show diag all eeprom detail • show platform software trace message iomd • show platform software agent iomd • show platform software peer shell-manager brief • show platform software peer chassis-manager • show platform software memory iomd • set platform software trace iomd Regulatory Compliance For regulatory compliance and safety information, see the Regulatory Compliance and Safety Information for the Cisco NCS 4200 Series Aggregation Routers document. Cisco NCS 4216 Hardware Installation Guide 22 Cisco NCS 4216 Overview Interface Numbering