Renewal of the School of Science and Engineering "Campus Network"
Titanet (Tokyo Institute of Technology Academic NETwork) — the School of Science and Engineering campus network that broadly covers the three sites of Ookayama, Suzukakedai (now: Yokohama), and Tamachi — evolved through the first-generation Titanet, SuperTitanet, and Titanet3, and then into Titanet4 (Titanet phase 4) over FY2019 to FY2021.
In this renewal, the campus wireless network was also revised at the same time: Titanet Wireless 2 (TW2) was integrated into Titanet4 and became Titanet4-wireless.
For the campus wireless network (Titanet4-wireless), the previously used tunnel-mode wireless LAN controller model was discontinued in favor of a cloud-type controller. This choice was made both to avoid tunnel aggregation becoming a bottleneck once Wi-Fi 6 was introduced, and to secure scalability for future access point expansion. With the wireless LAN system introduced this time (Cisco Meraki), integrated management of access points and PoE switches is achieved through a cloud console; a device can be put into operation simply by registering its serial number and providing, via DHCP, an IP configuration that can reach the cloud console. The cloud console allows the status of connected devices to be viewed in line with the required specifications, creating an environment where rapid incident response and similar tasks can be carried out.
The Titanet4 backbone inherits the design of its predecessor Titanet3, adopting a two-tier network configuration of core switches (backbone switches) and building switches (edge switches). Two core switches are placed at each of the Ookayama campus and the Suzukakedai (now: Yokohama) campus, and the cores are interconnected via inter-campus WDM using two 40G lines each — a total of 160 Gbps — configured as MC-LAG (Multi-Chassis Link Aggregation). Each edge switch connects to the two core switches within its campus via 40G lines, also in a redundant MC-LAG configuration, giving 80 Gbps between core and edge. Before MC-LAG was introduced, a function that blocked part of the links was used to avoid loops; with MC-LAG, the link bandwidth can now be used effectively.
For external connectivity, the configuration that previously operated only from the Ookayama campus was changed so that SINET connection (currently SINET6) over a 100G line is now also possible from the Suzukakedai (now: Yokohama) campus. In addition, separate 10G lines are provided, and connections to academic research networks/projects such as APAN and WIDE, as well as to commercial ISPs, continue, for a total external connectivity of 210 Gbps. On top of this, FLET'S VPN Wide provided by NTT East has been introduced as a backup for inter-campus communication, forming the operations network. For access control on the external-connection portion, a redundant set of security appliances is placed at the Ookayama campus, with attention given to security.
Titanet4 provides broad and powerful support for everything from cutting-edge research and development carried out on and off campus to administrative work at the university. Beyond that, it also serves as "infrastructure for infrastructure": an indispensable foundation for building the infrastructure that supports campus life in many situations, including the campus-wide authentication and authorization system, the remote lecture system, the video conferencing system, the room access control system, inter-campus extension telephones, and the electricity and water meter reading system.
Equipment Overview
The external-connection routers, core switches, and edge switches of Titanet4 use products from Juniper Networks (USA).
Titanet4 Equipment
| Role | Product |
|---|---|
| External-connection distribution switch | Arista 7280SR2, Arista 7280SE, Cisco Catalyst C3850-24XS |
| External-connection router | Juniper MX10003, Juniper MX304 |
| Inter-campus WDM equipment | ADVA FSP 3000R7, NTT Innovative Devices Plus Repeater Access |
| Core switch | Juniper EX9200 series — EX9214 (Ookayama), EX9208 (Yokohama) |
| Edge (building) switch | Juniper EX4300 series — EX4300-48MP, EX4300-32F, Cisco Catalyst C1000-24P-4X-L |
| Security appliance | FortiGate 2000E, Juniper SRX4600, Check Point MHS-6203-PLUS (CERT procurement) |
Titanet4 wireless Equipment
| Role | Product |
|---|---|
| PoE switch | Cisco Meraki MS355-24X2 |
| PoE switch | Meraki MS120-8FP |
| Wireless access point | Cisco Meraki MR44 |
| PoE extender | D-Link 2-Port Gigabit PoE Extender (DPE-302GE) |