www.python.org CDN Detection: Possible Fastly Usage

CNAME, HTTP header, and ASN signals indicate that www.python.org may be using Fastly, with 65% confidence. Review the evidence and latest check time.

Checked At: 10/27/2026, 16:20:56

Likely using Fastly

This result is based on public DNS, HTTP, and network signals and may update with later observations.

www.python.orgHTTP Status 200 10/27/2026, 16:20:56

Overall Confidence

65%Evidence strength

Based on the independent evidence matched in this detection

Node Distribution

Current snapshot

Fastly 65%

Detection Path

Complete · 5 stages

DNS Resolution

Complete · 6 addresses

CNAME Chain

Complete · 1 CNAME found

IP / ASN

Complete · 6 IPs, 4 ASNs

HTTP Response

Complete · response headers collected

Fingerprint Score

Complete · 4 evidence types

Evidence Timeline

Observed facts ordered by collection time

Checked At: 10/27/2026, 16:20:56

08:20:56 AM

CNAME

CNAME: dualstack.python.map.fastly.net

Fastly

Unknown

08:20:56 AM

HTTP

header: x-served-by

Fastly

Strong

08:21:48 AM

HTTP

header: x-served-by

Fastly

Strong

08:21:48 AM

HTTP

header: x-served-by

Fastly

Strong

08:21:48 AM

CNAME

CNAME: dualstack.python.map.fastly.net

Fastly

Unknown

Show 8 more evidence items

08:21:48 AM

HTTP

header: x-served-by

Fastly

Strong

08:21:48 AM

CNAME

CNAME: dualstack.python.map.fastly.net

Fastly

Unknown

08:21:51 AM

HTTP

header: x-served-by

Fastly

Strong

08:21:51 AM

CNAME

CNAME: dualstack.python.map.fastly.net

Fastly

Unknown

08:21:58 AM

HTTP

header: x-served-by

Fastly

Strong

08:21:58 AM

CNAME

CNAME: dualstack.python.map.fastly.net

Fastly

Unknown

08:21:59 AM

CNAME

CNAME: dualstack.python.map.fastly.net

Fastly

Unknown

08:21:59 AM

HTTP

header: x-served-by

Fastly

Strong

Score Explanation

Evidence strength breakdown

CNAME evidence

100 / 100

CNAME target and routing-domain signals

HTTP headers

100 / 100

Response header name and value matches

This score presents evidence strength, not statistical probability. A shared ASN or cloud network cannot confirm a CDN on its own.

Node and Routing Differences

Resolution results and access signals observed by region and carrier

Collected just now

Region	Carrier	Resolved IP	CDN Provider	ASN	Location	TTL	Confidence	TTFB
Northern China	中国电信	151.101.0.223/32	Fastly	-	中国北京市	-	65%	1179ms
Central node	-	151.101.64.223/32	Fastly	-	-	8s	65%	-
Eastern North America	Overseas	2a04:4e42:200::223/128	Fastly	-	美国波士顿	-	65%	13ms
Western North America	Overseas	151.101.64.223/32	Fastly	-	美国圣何塞	-	65%	99ms
Southwestern China	中国电信	2a04:4e42:400::223/128	Fastly	-	中国昆明市	-	65%	1200ms
East Asia	Overseas	151.101.64.223/32	Fastly	-	中国香港特别行政区香港	-	65%	124ms
Southern China	BGP多线	151.101.128.223/32	Fastly	-	中国广州市	-	65%	1297ms

Node results vary by region, carrier and time7 nodes

Detection results are inferred from public DNS and HTTP signals. Confidence reflects the strength of the matched evidence and does not imply 100% certainty.

FastlyPrimary candidate

Confidence 65%

CNAME: dualstack.python.map.fastly.net

header: x-served-by

CNAME: dualstack.python.map.fastly.net

header: x-served-by

CNAME: dualstack.python.map.fastly.net

header: x-served-by

CNAME: dualstack.python.map.fastly.net

header: x-served-by

CNAME: dualstack.python.map.fastly.net

header: x-served-by

CNAME: dualstack.python.map.fastly.net

header: x-served-by

View Fastly Performance Review

Methodology and limitations

Detection results are based on cross-referencing public DNS, HTTP response headers, and ASN signals; confidence indicates evidence strength and does not represent statistical accuracy.