Enterprise-level Japanese Native Ip Network Architecture Suggestions And Performance Optimization

1. goals and preliminary preparations

- clarify the goal: how many japanese native ips (/24, /23) are required, and whether local export, japanese computer room hosting, or hybrid multi-point deployment is required.
- prepare materials: company business license, contact person, technical contact person, estimated bandwidth, business purpose. it is recommended to prepare a list of alternative computer rooms and isps (ntt, iij, softbank, etc.).

2. obtain native ip and apply for asn

- purchase ip segments through japanese local isp or international lir: prioritize isp or hosting service provider that can provide japanese native outbound path. when making inquiries, confirm whether bgp announcements and subnet routing are supported.
- asn: if you want multi-homing or self-managed routing, apply for an asn from apnic or delegate through lir. in the short term, you can use isp to announce it on your behalf, but in the long term, it is recommended to have your own asn for traffic engineering.

3. computer room and interconnection selection

- select the computer room: tokyo (ty2/ty3) and osaka are given priority. select the nearest pop considering the user distribution.
- interconnection method: choose at least two upstreams (direct backbone + local isp) for multi-homing; use ix (jpnap, etc.) for peering if necessary to reduce latency and cost.

4. bgp basic configuration and security

- bgp session example (cisco ios): router bgp 65001; neighbor xxxx remote-as ; neighbor xxxx update-source loopback0;
- route filtering: implement inbound prefix-lists and route-map on the upstream, limit the maximum number of prefixes and verify rpki/roa. use ttl security, md5 passwords and bgp session prefix-lists.

5. traffic engineering practice

- local priority (local_pref): direct egress traffic by setting different local-preferences to different isps.
- community and med: cooperate with the upstream to use bgp community to control the neighbor's preference for your route, and use med to affect the other party's backhaul path. practical example: route-map set_local permit 10; set local-preference 200;

6. anycast and service deployment recommendations

- anycast deployment steps: configure the same arbitrary address in multiple pops in tokyo/osaka and advertise the same prefix, and implement nearest routing through bgp.
- notes: backend status synchronization (eg bgp+keepalived for vip), health check automatically revokes routes (use bgp flowspec or bfd+ automated revoke script).

7. cdn, geodns and dns architecture

- it is recommended to deploy authority locally in japan or use geodns service to guide traffic to the nearest pop, and cooperate with global cdn for static acceleration.
- dns configuration should be configured with low ttl and health detection to ensure that users can quickly switch exits during failover.

8. performance optimization network parameters

- mtu and path mtu: unify the mtu (usually 1500 or 9000) on the intranet and link, and enable pmtud.
- tcp tuning: set net.ipv4.tcp_congestion_control=cubic on the linux server and adjust the socket buffer (net.core.rmem_max, wmem_max) to adapt to long delay-high bandwidth links.

9. ddos protection and security strategy

- border protection: deploy ddos cleaning (traffic cleaning service or cloud/isp cleaning) upstream or locally, and combine it with bgp flowspec to deliver black holes or traffic filtering.
- acl and rate limiting: implement strict acl and sflow sampling on core routers, prohibit unauthorized management access, and enable ssh keys and springboards.

10. monitoring, alarming and capacity planning

- monitoring items: bgp session status, bandwidth usage, packet loss/delay, traffic distribution, tcp retransmission. tools: prometheus+grafana, netdata, zabbix, thousandeyes.
- capacity planning: plan bandwidth based on peak traffic + 30%, and perform traffic retrospective analysis and growth forecast regularly.

11. testing, switching and rollback process

- test scenarios: single point failover, link degradation, bgp route withdrawal test, anycast node offline. each test is written as a runbook and practiced in a non-production environment first.
- switching steps: first, gradually divert traffic during off-peak hours, observe and monitor for 30-60 minutes, and then switch completely; if abnormal, press the rollback runbook to withdraw bgp routing and restore the front-end configuration.

12. common commands and automation examples

- view bgp on linux (using frr/quagga): vtysh -c "show ip bgp summary"; bgp session test uses tcpdump to filter bgp port 179.
- automation: use ansible to manage router configuration fragments. before ci triggers bgp changes, run configuration lint and simulation in the test lab.

13. question: how to obtain the real japanese native ip and ensure that the route is exported in japan?

a: it is preferred to purchase ip or hosting services with a japanese local isp or a computer room provider in japan, requiring "japanese originated" or "announced from japan". at the same time, use the asn in japan or let the isp announce the route from the japanese pop, and cooperate with ix peering to verify the egress path.

14. question: how to quickly detect and handle route hijacking or anomalies in bgp configuration?

a: enable rpki/roa verification, set the maximum prefix limit, monitor abnormal as_path and route_change; when an abnormality is detected, you can immediately issue a black hole or revoke the announcement through the bgp community or flaps protection script and notify the upstream.

15. question: what practical suggestions are there for optimizing the delay for overseas users?

a: deploy static resources nearby in japan or use cdn, use anycast to reduce the number of hops; configure multi-homing + ix peering to optimize backhaul; adjust the tcp congestion algorithm and increase the window; consider dedicated lines or sd-wan to optimize link selection for transoceanic links.