Comoe NetworksMy Network Consultant

Home

Use cases

NOC Troubleshooting SOC Triage Incident Response Performance Analysis

Protocols · Network & transport

IP ICMP TCP UDP

Protocols · Web & infrastructure

HTTP TLS DNS DHCP

Protocols · Applications

SIP SMTP FTP LDAP Kerberos SMB2

Resources

PCAP Library Tcpdump Howto About FAQ

Resources · Library

Network packet capture library

A curated collection of real-world captures — from DNS queries to TCP errors and TLS alerts — each hand-picked to illustrate a key concept, protocol or anomaly.

Network packet capture library illustration

Explore captures designed to illustrate key networking concepts, protocols, and anomalies — built to support learning, troubleshooting, and deep analysis.

🔄 Updated regularly — new captures are added over time to reflect fresh concepts, attack patterns, and diagnostic scenarios. Perfect for network engineers, students, and curious explorers alike.

TCP examples

TCP simple session

A simple TCP flow with handshake, data transfer and closing.

Connection timeout

The TCP connection to a service has failed.

Connection aborted

The connection was aborted during the transfer of data.

Not RFC 7323 compliant

TCP window scale or timestamp option is missing.

TCP retransmission

TCP loss may degrade the performance of data transfer.

TCP fast retransmission

TCP loss may degrade the performance of data transfer.

TCP zero window

The receiver tells the sender to pause because its buffer is full.

Segment out of window

The segment is outside the receiver window (spurious retransmission is one case).

TCP spurious retransmission

An already-received segment is sent again.

DNS examples

Basic DNS query

Standard A-record request and response over UDP port 53.

Name error (NXDOMAIN)

A DNS name error occurred — the domain does not exist.

No server response

DNS queries did not get any response.

Server failure

The DNS server failed to process a query.

DNS retransmissions

Some DNS requests were retransmitted.

Truncated message

Some DNS messages exceeded the allowed size.

Request refused

A query was refused by the server.

DNSSEC

Security extensions that protect DNS from spoofing and cache poisoning.

ICMP examples

Server port unreachable

A service listening on UDP is not available.

ICMP ping losses

Ping is a tool used to measure latency and loss.

Client port unreachable

Client is not expecting any more server responses.

TLS examples

TLS handshake

Handshake including ServerHello, Certificate, and key exchange.

Alert: protocol version

Unsupported or deprecated TLS version.

Alert: decode error

Malformed or improperly formatted TLS message.

Alert: unknown CA

The Certificate Authority is not trusted.

Alert: handshake failure

Could not establish a secure connection during the TLS handshake.

Alert: internal error

Unexpected internal failure while processing a TLS handshake or data exchange.

Internet Protocol (IP) examples

Not ECT compatible

At least one peer is not ECN-Capable Transport (ECT) compatible.

TTL change

Different TTL values were observed within a session.

Multicast IP addresses

Multicast addresses send data to multiple devices simultaneously over an IP network.

We use cookies & process data
By using this site, you agree to our Terms and Privacy Policy. We process file uploads for network analysis only.