News/ Announcements
11 Mar 2015

IPv4 Address Renumbering for HKIX Public Peering LAN: 12-15 Jun 2015 HKT (Fri-Mon)

Dear HKIX Participants,

This year is the 20th Anniversary of HKIX, which was set up in 1995.  HKIX has experienced steady growth during the last 20 years.  To cope with the growth, a lot of changes and upgrades had been done already.  For the IPv4 address block currently used for HKIX Public Peering LAN (202.40.160/23), we have already used up more than 80%.  In order to cope with the continuous growth of HKIX and having learnt from the experience of other IXPs around the world, we have decided to perform IPv4 address renumbering for HKIX Public Peering LAN during 12-15 Jun 2015 HKT.  This is the only option for solving the problem while minimizing the impact to the HKIX community.

A NEW IPv4 address block will be used and the network mask of HKIX public peering LAN will be changed from /23 to /21.  All HKIX participants will have to re-configure the IPv4 addresses on their routers in order to use the new IPv4 addresses to do peering over HKIX. 

During the 4-day migration (12-15 Jun 2015 HKT), HKIX will do parallel-run of both new and old IPv4 address blocks.  HKIX new route servers will serve the multilateral peering for new address block while the existing route servers will serve the multilateral peering for old address block.  HKIX participants can change their peering IPs at any time during the 4-day migration period and the old HKIX route servers and the old IPv4 address block 202.40.160/23 will cease operations right after completion of the IPv4 address renumbering on 15 Jun 2015 HKT.

Pre-announcement of this migration was made during APRICOT-APAN 2015 held in Fukuoka last week at “Peering Forum (2)” and “Lightning Talks” sessions.  Please refer to the following links:


To obtain the detailed arrangement for IPv4 address renumbering, please provide the following information to HKIX-NOC (hkix-noc@cuhk.edu.hk):

Your ASN:
Your IPv4 address(es) at HKIX:
Your email contact for the IPv4 address renumbering:

HKIX-NOC will contact you by email individually after receiving information from you.
Thank you very much for your cooperation on this migration.  Let us work together to make it a successful one.

Best regards,

P.S.  There will be no change to IPv6 address block used for HKIX Public Peering LAN.


 Application to Connect

 Site Access Procedures

 Request for Filter Update

 HKIX Switching Statistics

 Schedule Maintenance Schedule Maintenance


1 Mar 2015

New participants connected to HKIX

We are pleased to announce that Criteo, EFLY Network Limited and Incapsula have been directly connected to HKIX. Please visit our Participants page to learn more about them.

1 Dec 2014

New participants connected to HKIX

We are pleased to announce that Emirates Telecommunications Corporation (ETISALAT) , Sony Corporation of Hong Kong Limited,  ViaNet Group Limited have been directly connected to HKIX. Please visit our Participants page to learn more about them.

28 Nov 2014

Production of the Second HKIX Core Site HKIX1b Starting 28 Nov 2014

In order to enhance the reliability and scalability of HKIX to cater for the ever-growing demands from the local as well as the regional and global Internet industry players for more stable and higher-speed interconnection services, HKIX has adopted a new Dual-Core Two-Tier Architecture and has established a second core site called HKIX1b within the campus of CUHK with the following characteristics:

  • The original core site HKIX1 and the new core site HKIX1b are separated by more than 1.5km in terms of fiber distance within CUHK campus
  • Both sites contain Core Switches and Access Switches interconnected by multiple 100GE links
  • Both sites are running in Active-Active mode
  • Access Switches at both HKIX1 and HKIX1b can serve connections of GE/10GE/100GE from participants
  • Both sites together provide card resilience, chassis resilience as well as site resilience
  • The architecture is highly scalable and can support more satellite sites outside of CUHK campus

Starting from 28 Nov 2014, the new core site HKIX1b is in production and ready for accepting connections from HKIX participants.  Participants are encouraged to take advantage of the dual-core architecture for better resilience by connecting to both core sites.

For details about the HKIX Dual-Core Two-Tier Architecture, please refer to the presentations at http://www.hkix.net/hkix/presentation.htm.


27 Nov 2014

DDoS Mitigation Trial via HKIX Route Servers by Supporting IPv4 Special Host Route Announcements for Black-holing

With immediate effect, HKIX route servers support IPv4 special host route announcements (i.e. /32’s) with BGP community 4635:666 for DDoS Mitigation Trial.  If HKIX participants want to participate, please send email to hkix-core@itsc.cuhk.edu.hk for implementation details.

In short, trial participants should at least accept the /32’s with BGP community 4635:666 from HKIX route servers and then do black-holing for traffic destined to those IP addresses.  Trial participants can also announce /32’s which are under their managed address blocks with BGP community 4635:666 to signal other trial participants to do black-holing when under DDoS attacks.

Benefits of participating:

  • Hosts which are not DDoS targets will be less affected by the DDoS attacks.
  • All participating networks will save some bandwidth of their HKIX connections during the DDoS attack period.

Possible impacts to DDoS Victims:

  • The relevant hosts will be unreachable from those participating networks while the special /32 route announcements are in effect.

If the trial is considered successful, the set-up will be made permanent and this will be one of our standard services to all HKIX participants.

Again, if HKIX participants want to participate, please send email to hkix-core@itsc.cuhk.edu.hk for implementation details. 

We look forward to working with all of you to do better DDoS mitigation over HKIX.

Best regards,



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