Cisco 1100 Series Router Buying Guide: C111x, C1121, TG & IR1101

Cisco 1100 Series platforms put IOS XE branch routing, a small Gigabit LAN switch, optional Wi-Fi or LTE, and SD-WAN readiness into a fanless chassis. The same category also holds two cousins you must not confuse with branch CPE: C1100TG terminal gateways and the industrial IR1101. Match the PID to the job—branch edge, console server, or rugged IoT—to avoid expensive returns.

This guide covers our Cisco 1100 Series Routers listings: C1101 / C1111 / C1112 / C1121 branch ISRs, C1100TG async gateways, and IR1101. For the wider ISR landscape see the Cisco ISR Router Buying Guide. Older fixed CPE lives in the 800 Series catalog; campus switching is covered in the Cisco Switch Buying Guide.

Three product lines share one category page

Cisco’s ISR 1000 / 1100 branch family, the 1100 Terminal Services Gateway, and the Catalyst IR1101 rugged router all appear under “1100” in catalogs. Treat them as separate BOMs:

• Branch ISR (C1101, C1111, C1112, C1121): Fanless IOS XE routers with fixed GE LAN ports, one or two GE WAN interfaces, optional embedded LTE/Wi-Fi or a pluggable PIM slot. Ideal for SMB / small-enterprise branches and SD-WAN edges.
• Terminal gateway (C1100TG): Rack-oriented async console servers with up to 32 onboard RS-232 ports (expandable toward 72 with daughtercard + NIM). Not a substitute for a C1111 branch router.
• Industrial IR1101: Modular rugged router with four 10/100 FE LAN ports, a GE combo WAN, wide DC input, and industrial temperature ratings—built for utilities, transportation, and outdoor cabinets.

Decode the ISR 1000 / 1100 part number

Cisco’s ISR 1000 naming is consistent once you see the pattern:

• C1101 — one GE WAN; C1111 / C1121 — two GE WAN (one typically RJ-45/SFP combo plus one RJ-45).
• C1112 — one GE WAN/SFP plus G.FAST / VDSL2 / ADSL2+ Annex B/J over ISDN.
• -4P / -8P — four or eight Gigabit Ethernet LAN switch ports.
• X (as in C1111X, C1121X) — 8 GB DRAM and 8 GB flash for app hosting and heavier SD-WAN security stacks; base models ship with 4 GB / 4 GB. Memory is not field-upgradeable.
• LTEEA — embedded Category 6 LTE for EMEAR and North America; LTEP — pluggable PIM slot (modem ordered separately).
• W plus a domain letter (WB = -B United States) — embedded 802.11ac Wave 2 AP. A base -8P without W has no Wi-Fi.

Ignore marketplace titles that say “10G” or claim Wi-Fi on a non-W PID. Cisco’s data sheet lists Gigabit Ethernet WAN/LAN on these platforms; use the PID, not the marketing string.

Compare the branch models you will quote

C1101: smallest IOS XE Ethernet edge

The C1101-4P is Cisco’s compact ISR 1101: one copper GE WAN, four GE LAN ports, micro-USB console, USB 3.0, fixed 4 GB DRAM/flash, and a fanless ~1.1 × 7.5 × 6.0 in chassis. Cisco documents about 475 Mbps max encrypted IMIX and SD-WAN IPsec up to roughly 450 Mbps (512-byte) on the 1101 class—size from concurrent services, not the ceiling alone.

C1101-4PLTEP adds a PIM slot for pluggable LTE/5G (CAT4–CAT18 and Sub-6 per Cisco). Order modem, antennas, and carrier SKU separately—the bare LTEP chassis is not a complete cellular solution.

C1111 and C1121: dual-WAN branch workhorses

For fiber or copper Metro Ethernet with a second GE handoff, start with the dual-WAN platforms.

• C1111-4P — four GE LAN; two GE WAN (combo RJ-45/SFP + dedicated RJ-45); optional PoE (2× PoE or 1× PoE+ with the 115 W supply).
• C1111-8P — eight GE LAN and the same dual GE WAN layout; optional 4× PoE / 2× PoE+ with the 150 W supply. Despite some listing titles, the base C1111-8P has no Wi-Fi.
• C1111X-8P — C1111-8P with 8 GB DRAM/flash when you need app hosting or SD-WAN advanced security headroom.
• C1111-4PWB — four-port C1111 with embedded dual-band 802.11ac Wave 2 for the -B (United States) domain; our listing is refurbished.
• C1111-8PLTEEA — eight LAN ports plus embedded CAT6 LTE for EMEAR/North America (refurbished in catalog).
• C1111-8PLTEEAWB — LTE EA plus Wi-Fi domain B when one chassis must terminate cellular and local wireless (refurbished).
• C1121-4P / C1121-8P / C1121X-8P — Cisco’s 1121 dual-GE WAN family with 4 or 8 LAN ports; the X model carries 8 GB memory. Cisco rates C112x-8P class SD-WAN IPsec up to about 700 Mbps (512-byte) and C1121-4P about 450 Mbps. Prefer Cisco’s GE specs over titles that incorrectly say “10G” or “8GB” on non-X four-port units.

Order SFPs from Transceivers for the combo WAN, and confirm PoE power under Cisco Power Supplies. For denser or Wi-Fi 6 coverage, pair a wired 1100 with dedicated APs—see our wireless AP buying guide.

C1112: DSL plus LTE when copper is the primary WAN

C1112-8PLTEEA combines eight GE LAN ports, one GE RJ-45/SFP WAN, a G.FAST-capable DSL interface (Annex B/J over ISDN per Cisco’s 1112 definition), and embedded LTE EA. Use it when the carrier’s last mile is DSL and you still want cellular failover in the same fanless box—common on European ISDN copper plants. Confirm annex, vectoring, and SIM region on the RFQ before you freeze the PID.

C1100TG: terminal services gateways (not branch routers)

The C1100TG-1N24P32A is a Terminal Services Gateway with 32 onboard RS-232 async ports (up to 230 kbps), a 24-port L2 GE switch, and one NIM slot. C1100TG-1N32A keeps the 32 async ports and NIM without the switch. Expand toward 48 with C1100TG-16A and up to 72 with NIM-16A/24A plus CAB-ASYNC-8 cables. Use these for OOB console aggregation—not as a C1111 replacement.

IR1101: industrial rugged edge

IR1101-K9 is the Catalyst IR1101 base: four 10/100 FE LAN ports (not Gigabit, despite some titles), GE combo WAN, RS-232 serial, 4 GB DRAM/flash, IP30, and DC input about 9.6–60 V. Cisco rates sealed-cabinet use from -40 to 60 °C (higher with airflow). Plan expansion modules and industrial SFPs under Cisco Expansion Modules.

Licensing and SD-WAN notes that affect the quote

ISR 1000 / 1100 platforms ship with IOS XE Universal and IP Base. SEC, APP, VPERF, HSEC, or Cisco DNA / SD-WAN subscriptions unlock VPN scale and encrypted throughput. With IP Base + SEC alone, Cisco shapes encrypted traffic at 50 Mbps until a performance license raises or removes that shaper—confirm Smart Account entitlements on new and refurbished units. DRAM/flash are fixed; choose an X PID up front for 8 GB.

When to keep 800/900 versus buy 1100

Keep 800 Series for like-for-like DSL/LTE spares. Step to 1100 for IOS XE, SD-WAN, Gigabit LAN switching, pluggable cellular, or longer lifecycle. Also compare Cisco Routers, Cisco ISR, and 900 Series. Voice endpoints pair with our IP Phone & Collaboration guide; switch path decisions can use Meraki MS vs Catalyst 9000.

Pre-RFQ checklist

• Job type: branch ISR vs terminal gateway vs industrial IR1101
• WAN media: copper GE, SFP fiber, DSL annex, and/or LTE region (EA vs LA vs pluggable)
• LAN port count (4 vs 8), PoE need, and whether Wi-Fi belongs on-box or on dedicated APs
• Memory: 4 GB base vs 8 GB X for app hosting / advanced SD-WAN
• SEC/APP/HSEC or DNA subscription entitlements and Smart Account readiness on refurbished SKUs
• SFPs, async cables (CAB-ASYNC-8 for TG), LTE antennas, PoE PSU, quantities, cutover date

FAQ