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Autonomous System

AS15305 ยท Syringa Networks, LLC

Overview

AS15305 is announced on the Internet: RIPE RIS route collectors currently see 26 IPv4 prefixes and 1 IPv6 prefix originated by this network. Together, its IPv4 prefixes cover 55,040 addresses, with overlapping prefixes counted once. In the paths the collectors record, it has 6 upstream neighbours (transit providers or peers) and 55 downstream neighbours (customers or networks it carries). Its most visible upstreams are Arelion Sweden AB (AS1299), Cogent Communications, LLC (AS174), and Hurricane Electric LLC (AS6939). AS15305 was assigned by ARIN, and its registration country is United States.

Source: RIPEstat (RIPE NCC), RIS route collectors. Read on October 17, 2026 at 3:15 AM UTC. This page is refreshed at most every 12 hours.

Go further

The trace goes to 208.98.128.1, the first address of 208.98.128.0/18. An address picked inside a prefix may not answer (nothing listens there, or the network filters probes): the trace then shows the path up to the last network that replies.

Announced prefixes

IPv4 prefixes (26 prefixes)

PrefixAddresses
45.33.222.0/23512
64.136.100.0/221,024
66.232.64.0/198,192
67.215.32.0/204,096
69.59.31.0/24256
104.245.20.0/221,024
151.122.232.0/24256
158.120.248.0/221,024
161.115.208.0/204,096
162.57.146.0/23512
173.224.176.0/204,096
192.35.255.0/24256
198.60.192.0/24256
198.199.151.0/24256
198.199.152.0/23512
199.5.221.0/24256
199.244.14.0/23512
204.8.52.0/221,024
204.10.184.0/24256
204.99.153.0/24256
204.99.154.0/23512
206.168.83.0/24256
208.98.128.0/1816,384
209.25.172.0/221,024
209.141.112.0/204,096
216.182.96.0/204,096

IPv6 prefixes (1 prefix)

Prefix
2605:5800::/32

Neighbours

Upstreams (transit or peers) (6)

ASNetworkVisibility
AS1299Arelion Sweden AB5,759
AS174Cogent Communications, LLC3,415
AS6939Hurricane Electric LLC3,001
AS3303Swisscom (Schweiz) AG290
AS209CenturyLink Communications, LLC14
AS8966EMIRATES TELECOMMUNICATIONS GROUP COMPANY (ETISALAT GROUP) PJSC1

Downstreams (customers) (55)

ASNetworkVisibility
AS19218Midvale Telephone Exchange, Incorporated622
AS26223Silver Star Communications536
AS397285Cambridge Telephone511
AS54847Custer Telephone Cooperative, Inc.476
AS32922ATC Communications449
AS20295Filer Mutual Telephone Company448
AS16957Idaho Power Company447
AS30530Farmers Mutual Telephone Company443
AS395846Direct Communications Rockland, Inc416
AS23389Campbell Scientific, Inc.388
AS30663-357
AS46528-323
AS210-320
AS395107-281
AS397268-259
AS397740-257
AS14971-256
AS54885-256
AS394741-256
AS19546-252
AS393898-252
AS396094-252
AS398867-252
AS402321-250
AS10753-248
AS46133-242
AS21947Blackfoot Telephone Cooperative, Inc.235
AS396056-222
AS393940-200
AS402277-200

The 30 most visible of 55.

7 more neighbours appear on both sides of this network depending on the path, so they are counted in neither list.

Visibility is RIPEstat's count of how often the route collectors observed the link. It compares neighbours with each other; it is not a traffic volume.

How to read this page

An Autonomous System (AS) is a network run under one routing policy: an internet provider, a cloud, a content network, a university. Each one has a number, its ASN, assigned by a regional registry (ARIN, RIPE NCC, APNIC, LACNIC, AFRINIC), and uses BGP, the protocol networks use to tell each other where addresses are, to announce the blocks of addresses it delivers to.

A prefix such as 203.0.113.0/24 is a block of addresses: the number after the slash says how many bits are fixed, so a /24 holds 256 IPv4 addresses and a /16 holds 65,536. Networks often announce a large block and smaller pieces of it at the same time, which is why the address total counts each address once.

Neighbours come from the paths themselves. A network that appears just before this one in a path, on the collector's side, is an upstream: a transit provider or a peer. One that appears just after it is a downstream, usually a customer. Peering at an internet exchange also shows up as an upstream, so the upstream list is not a list of paid transit.

The data comes from RIPEstat, run by the RIPE NCC, which gathers the routing tables of hundreds of networks through its RIS route collectors. This page reads it when it is visited and keeps it for 12 hours at most; the BGP viewer reads it live.

Frequently asked questions

How do I find the ASN of an IP address?
Type the address in the BGP viewer: it shows the prefix that covers it, the AS that originates that prefix and the paths seen towards it. A traceroute also names the network of each hop, so you can see every AS a connection crosses.
Why does one company have several ASNs?
Large operators split their network by region, by activity or by history: a cloud may use one number for its backbone and another for a region, and every acquisition brings its own numbers. Each number has its own page, with its own prefixes and neighbours.
Why do prefix counts differ from one site to another?
Each source sees the routing table from different collectors, at a different time, and counts differently: some include prefixes withdrawn in recent weeks, some merge a block and its pieces. This page counts the prefixes RIPE RIS collectors see originated by the network at the end of the latest two-week window, and counts each IPv4 address once.
Is this the list of IP ranges of a cloud provider?
It is what its networks announce, which is what the Internet routes to them. Many providers also publish an official list of ranges per service and region; that list is the reference for firewall rules, because a range can be announced before it is used, or announced by another of their AS numbers.