Autonomous system
AS11647 SENTEX-NET
Unclassified ARIN
Summary
Sentex Communications Corporation
isp legacy
SENTEX-NET is Sentex Communications, a long-established independent internet provider based in Cambridge, Ontario, serving southwestern Ontario. RIS sees 32 IPv4 prefixes and about 23,300 addresses, 2 IPv6 prefixes (2607:f3e0::/32 and a /48), and 14 observed BGP neighbours.
What it's used for
Regional access and business connectivity. The reverse DNS is the clearest evidence of what the space carries: names like p4j.xDSL-1mm.sentex.ca, dimplex-dsl.sentex.ca and 67-43-136-5.agas1a-dynamic.dsl.sentex.ca are subscriber access, with an explicitly dynamic DSL pool among them, while dw3-lo0.sentex.ca, dw4blo0.sentex.ca and ipsec-test.sentex.ca are the operator's own routers and service hosts. This is an eyeball network with a substantial business-access side, not a pure enterprise and not a wholesale carrier — 14 neighbours is a mid-sized ISP with several upstreams and peering, an order of magnitude short of a transit provider.
The prefix registrants deserve a careful read rather than an alarm. Most blocks register to Sentex itself (SENTEXCO, SENTEXCO2), but three register to other companies: Com Dev Ltd., Toy Com, and Junior Mine Services Ltd. These are not a leased-address tell. They are ordinary SWIP reassignments to named business customers — the pattern of an ISP that has been assigning space to local firms for decades — and the reverse DNS confirms it: 199.71.252.5 answers as eldon.toy.com, a customer running its own naming, while addresses inside the Junior Mine block still answer under sentex.ca.
Notable
Com Dev was a Cambridge, Ontario space-hardware manufacturer, which is about as local a customer as a Cambridge ISP could have. Customer names preserved in the registry are a kind of fossil record of a regional provider's history.
This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy. Source, and how to suggest an edit.
Interconnection
Peering at a glance
Internet exchanges
Recorded at 1 exchange in 1 country, largest first.
| Exchange | Location | Their address |
|---|---|---|
| Toronto Internet Exchange | Toronto, Canada | 206.108.34.18 |
Transit providers
9 upstream, 0 downstream and 14 adjacent networks observed; most-used upstreams first.
Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-11, licensed CC BY-NC-SA 3.0. Transit is inferred from observed BGP paths, never declared by either party.
Address space
Summary
IPv4 24 prefixes · 23.30K addresses IPv6 2 prefixes
| Country | Name | Prefixes |
|---|---|---|
| CA | Canada | 26 |
Registry
Allocation record
- Registry
- ARIN
- Handle
AS11647- Registry name
- SENTEX-NET
- Registrant
- Sentex Communications Corporation
- Abuse contact
- support@sentex.net
- Registered
- 1998-11-03
- Last changed
- 2012-03-02
- Allocation
- assigned
Routing security
RPKI and IRR
- RPKI
- 0% valid · 0 valid, 34 with no ROA
- ROAs
- 0 authorising AS11647
- ASPA
- no ASPA record
- IRR
- 97% registered · 33 of 34 announcements
- Route objects
- 43 naming AS11647
Reputation
Classification and threat
Unclassified Not in the curated lists. Most of the ~80,000 allocated ASNs are not.
Spamhaus DROP
Not on ASN-DROP The network as a whole is not listed.
No DROP prefixes None of its announced space is on the DROP prefix list.
Spamhaus DROP ("Don't Route Or Peer") lists space and networks run by, or hijacked for, spam and cybercrime operations: 431 networks and 1,768 prefixes, as published 2026-10-12. A short, high-confidence list, so a match is worth taking seriously, and absence from it says little on its own.
FBI IC3
No IC3 indicators Nothing from the FBI IC3 feed.
IC3 threat data is alpha. Absence of an indicator is not evidence of good behaviour, only of absence from this one feed.
Elsewhere