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Hands-On Network Programming with C

You're reading from   Hands-On Network Programming with C Learn socket programming in C and write secure and optimized network code

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Product type Paperback
Published in May 2019
Publisher Packt
ISBN-13 9781789349863
Length 478 pages
Edition 1st Edition
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Author (1):
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Lewis Van Winkle Lewis Van Winkle
Author Profile Icon Lewis Van Winkle
Lewis Van Winkle
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Toc

Table of Contents (25) Chapters Close

Preface 1. Section 1 - Getting Started with Network Programming FREE CHAPTER
2. Introducing Networks and Protocols 3. Getting to Grips with Socket APIs 4. An In-Depth Overview of TCP Connections 5. Establishing UDP Connections 6. Hostname Resolution and DNS 7. Section 2 - An Overview of Application Layer Protocols
8. Building a Simple Web Client 9. Building a Simple Web Server 10. Making Your Program Send Email 11. Section 3 - Understanding Encrypted Protocols and OpenSSL
12. Loading Secure Web Pages with HTTPS and OpenSSL 13. Implementing a Secure Web Server 14. Establishing SSH Connections with libssh 15. Section 4 - Odds and Ends
16. Network Monitoring and Security 17. Socket Programming Tips and Pitfalls 18. Web Programming for the Internet of Things 19. Answers to Questions 20. Setting Up Your C Compiler on Windows 21. Setting Up Your C Compiler on Linux 22. Setting Up Your C Compiler on macOS 23. Example Programs 24. Other Book You May Enjoy

Chapter 8, Making Your Program Send Email

  1. What port does SMTP operate on?

SMTP does mail transmission over TCP port 25. Many providers use alternative ports for mail submission.

  1. How do you determine which SMTP server receives mail for a given domain?

The mail servers responsible for receiving mail for a given domain are given by MX-type DNS records.

  1. How do you determine which SMTP server sends mail for a given provider?

It's not possible to determine that in the general case. In any case, several servers could be responsible. Sometimes these servers will be listed under a TXT-type DNS record using SPF, but that is certainly not universal.

  1. Why won't an SMTP server relay mail without authentication?

Open relay SMTP servers are targeted by spammers. SMTP servers require authentication to prevent abuse.

  1. How are binary files sent as email attachments when SMTP is...
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