Port 1477Microsoft SNA Server

Legacy SNA Server traffic for connectivity between Microsoft systems and IBM SNA host environments.

transport: tcp · udp
in transit: cleartext
assignment: official
risk: 6/10
lookups: 0

also known as ms-sna-server

Technical Details

what runs on :1477

Microsoft SNA Server uses TCP and UDP port 1477 for proprietary client/server and discovery or coordination traffic associated with SNA connectivity. The traffic is not ordinary IP-based SNA and does not have a broadly documented, interoperable wire format like HTTP; framing and session behavior are defined by Microsoft's SNA Server implementation. Related deployments may use additional SNA Server ports, including port 1478, for other server functions. Normal legacy deployments should not be assumed to encrypt this traffic by default.

Security Information

exposure of :1477

risk score

6/ 10risk

treat as sensitive. widely scanned and regularly exploited when reachable — restrict it to known sources.

network services averages 2.6 across 1,625 ports — this one sits 3.4 above.

in transit

cleartext

credentials and payloads are readable by anyone on path

assignment

official

registered with iana for this service — scanners fingerprint it by number

reachable over

tcp · udp

udp is connectionless — source addresses are trivially spoofed and it is a reflection favourite

security overview

This is a legacy enterprise integration service and should normally be restricted to trusted internal networks or protected through a VPN and firewall. Internet exposure can reveal a legacy SNA/Host Integration Server endpoint and may permit unauthorized connection attempts against an obsolete product; cleartext or weakly protected session traffic may also expose credentials or application data.

Record

iana registry entry

port: :1477
service: Microsoft SNA Server
transport: TCPUDP
encryption: cleartext
assignment: iana registered
risk: 6/10risk
category: Network Services System
usage: This port is used by Microsoft SNA Server, later known as Host Integration Server, to provide client and host-integration connectivity between Windows systems and IBM SNA environments. It is mainly encountered inside legacy enterprise networks rather than on public internet hosts.
lookups: 0rank 993
added: 2026-08-27
updated: 2026-09-22
references: IANA service name registry — port 1477

Something wrong?

This record is maintained by the engineers who use port 1477. Every field on it is editable — change what's wrong, say how you know, and a reviewer publishes it, usually within a minute. Last touched 2026-09-22.

01edit any field on a page of its own
02a model checks it for accuracy and spam
03clean and confident goes live immediately

edit this record →back to the registry

Related Ports

all 1,625 in network services →

the 8 most looked-up other ports in network services — 1,625 ports carry that label.

port	service	proto	category	risk	views
:9080	Groove RPC	TCPUDP	Web Services	caution	70.8k
:6543	Jetnet	UDP	Network Services	caution	65.3k
:5938	TeamViewer	TCPUDP	Remote Access	caution	65.0k
:8291	Winbox MikroTik Admin	TCP	Security	caution	62.9k
:3233	WhiskerControl Protocol	TCPUDP	Network Services	caution	61.9k
:3268	Microsoft Global Catalog (GC)	TCPUDP	Security	caution	54.6k
:135	Microsoft EPMAP	TCPUDP	Security	caution	51.9k
:3128	Tatsoft Default HTTP Proxy	TCP	Web Services	caution	46.8k

risk mix of the 8 listed

caution100%

0 of 8 encrypted

Port :1477Microsoft SNA Server

Technical Details

Security Information

Related Ports

Port 1477Microsoft SNA Server