SlideShare a Scribd company logo
1 of 15
Download to read offline
Simple mail transfer protocol
Overview
• Introduction to SMTP
• History of Smtp
• General features of SMTP
• Sendmail
• Relays And Gate ways
• How SMTP works
• Limitations in SMTP
• Example of SMTP
3
4
Composes, reads,
replies to
,forwards and
handles mailboxes
Transfers mails
from one host to
another
Collects mail
and delivers to
user agent
Transfers mails
from one host to
another
Collects mail
and delivers to
user agentIntroduction…
Introduction to SMTP
• SMTP is an Internet standard for electronic mail.
• SMTP is the protocol in widespread use today.
• It is the actual protocol used to transfer mail from MTA to
MTA.
• MTA: Mail Transfer Agent .... A program that actually
routes and delivers mail.
• MUA: Mail User Agen t ... A program that is used to
access mail after delivery.
• The objective of SMTP is to transfer mail reliably and
efficiently.
History of SMTP
• The SMTP specification originally started with the Mail
Transfer Protocol in 1980
• It evolved into Simple Mail Transfer Protocol (SMTP) in 1981
• Specified in RFC 821
• Most recent RFC is 2821
• First and most important implementation is sendmail
General Features
• Independent of underlying transmission subsystem.
• Just needs a reliable ordered data stream channel.
• Operates over TCP port 25.
• Uses an request-response protocol that is useful to human
readers (SMTP commands).
• SMTP sessions are stateful, with both parties carefully
maintaining a common view of the current state.
8
Sendmail
Mail Transfer Agent [MTA] : is a computer program or software agent
that transfers electronic mail messages from one computer to another.
• Sendmail is a MTA
• Supports several mail transfers including SMTP
• Pro’s
• Can perform header rewriting, mail routing
• Extensive support available
• Con’s
• Not secure
• Code is bulky [compared to other MTA’s such as qmail]
9
Message transfer…
SMTP is a push
protocol
10
• SMTP server can also
assume the role of a
“relay”
• SMTP mail gateways
are used to transport
mail prepared by a
protocol other than
SMTP
Relays and Gateways
SMTP supported
Non-SMTP
supported
11
Link Layer PCI IP-PCI
Keyword: argument(s)
Command format:
Response format:
3-digit status code [textual information]
How SMTP works?
Link Layer PCI IP-PCI TCP-PCI SMTP command/responseTCP-PCI SMTP command/responseTCP-PCI SMTP command/response
12
How SMTP works : Status Codes
The Server responds with a 3 digit code that may be followed
by text info
– 2## - Success
– 3## - Command can be accepted with
more information
– 4## - Command was rejected, but error
condition is temporary
– 5## - Command rejected, Bad User!
13
Limitations in SMTP
• Only uses NVT 7 bit ASCII format
– How to represent other data types?
• Susceptible to misuse (Spamming,
faking sender address)
SMTP transport example
Simple mail transfer protocol

More Related Content

What's hot

Imap(internet massege access protocaols)
Imap(internet massege access protocaols)Imap(internet massege access protocaols)
Imap(internet massege access protocaols)shashikant pabari
 
HyperText Transfer Protocol (HTTP)
HyperText Transfer Protocol (HTTP)HyperText Transfer Protocol (HTTP)
HyperText Transfer Protocol (HTTP)Gurjot Singh
 
Lecture 9 electronic_mail_representation_and_transfer
Lecture 9 electronic_mail_representation_and_transferLecture 9 electronic_mail_representation_and_transfer
Lecture 9 electronic_mail_representation_and_transferSerious_SamSoul
 
SMTP - SIMPLE MAIL TRANSFER PROTOCOL
SMTP - SIMPLE MAIL TRANSFER PROTOCOLSMTP - SIMPLE MAIL TRANSFER PROTOCOL
SMTP - SIMPLE MAIL TRANSFER PROTOCOLVidhu Arora
 
Introduction to HTTP protocol
Introduction to HTTP protocolIntroduction to HTTP protocol
Introduction to HTTP protocolAviran Mordo
 
Https presentation
Https presentationHttps presentation
Https presentationpatel jatin
 
transfer protocols,ftp,smtp,pop,imap
transfer protocols,ftp,smtp,pop,imaptransfer protocols,ftp,smtp,pop,imap
transfer protocols,ftp,smtp,pop,imapAKSHIT KOHLI
 
TCP - IP Presentation
TCP - IP PresentationTCP - IP Presentation
TCP - IP PresentationHarish Chand
 
Transport Layer Security (TLS)
Transport Layer Security (TLS)Transport Layer Security (TLS)
Transport Layer Security (TLS)Arun Shukla
 
TCP - Transmission Control Protocol
TCP - Transmission Control ProtocolTCP - Transmission Control Protocol
TCP - Transmission Control ProtocolPeter R. Egli
 
An overview of TCP (Transmission Control Protocol)
An overview of TCP (Transmission Control Protocol)An overview of TCP (Transmission Control Protocol)
An overview of TCP (Transmission Control Protocol)Ammad Marwat
 

What's hot (20)

Mail server
Mail serverMail server
Mail server
 
Smtp protocol
Smtp protocolSmtp protocol
Smtp protocol
 
Imap(internet massege access protocaols)
Imap(internet massege access protocaols)Imap(internet massege access protocaols)
Imap(internet massege access protocaols)
 
Http Introduction
Http IntroductionHttp Introduction
Http Introduction
 
SNMP/SMTP/MIME
SNMP/SMTP/MIMESNMP/SMTP/MIME
SNMP/SMTP/MIME
 
HyperText Transfer Protocol (HTTP)
HyperText Transfer Protocol (HTTP)HyperText Transfer Protocol (HTTP)
HyperText Transfer Protocol (HTTP)
 
Lecture 9 electronic_mail_representation_and_transfer
Lecture 9 electronic_mail_representation_and_transferLecture 9 electronic_mail_representation_and_transfer
Lecture 9 electronic_mail_representation_and_transfer
 
Http Vs Https .
Http Vs Https . Http Vs Https .
Http Vs Https .
 
TCP/IP and UDP protocols
TCP/IP and UDP protocolsTCP/IP and UDP protocols
TCP/IP and UDP protocols
 
SMTP - SIMPLE MAIL TRANSFER PROTOCOL
SMTP - SIMPLE MAIL TRANSFER PROTOCOLSMTP - SIMPLE MAIL TRANSFER PROTOCOL
SMTP - SIMPLE MAIL TRANSFER PROTOCOL
 
Introduction to HTTP protocol
Introduction to HTTP protocolIntroduction to HTTP protocol
Introduction to HTTP protocol
 
Https presentation
Https presentationHttps presentation
Https presentation
 
transfer protocols,ftp,smtp,pop,imap
transfer protocols,ftp,smtp,pop,imaptransfer protocols,ftp,smtp,pop,imap
transfer protocols,ftp,smtp,pop,imap
 
TCP - IP Presentation
TCP - IP PresentationTCP - IP Presentation
TCP - IP Presentation
 
Http-protocol
Http-protocolHttp-protocol
Http-protocol
 
Email security
Email securityEmail security
Email security
 
HTTP Basics
HTTP BasicsHTTP Basics
HTTP Basics
 
Transport Layer Security (TLS)
Transport Layer Security (TLS)Transport Layer Security (TLS)
Transport Layer Security (TLS)
 
TCP - Transmission Control Protocol
TCP - Transmission Control ProtocolTCP - Transmission Control Protocol
TCP - Transmission Control Protocol
 
An overview of TCP (Transmission Control Protocol)
An overview of TCP (Transmission Control Protocol)An overview of TCP (Transmission Control Protocol)
An overview of TCP (Transmission Control Protocol)
 

Similar to Simple mail transfer protocol

Similar to Simple mail transfer protocol (20)

how email works
how email workshow email works
how email works
 
Computer networks unit v
Computer networks    unit vComputer networks    unit v
Computer networks unit v
 
Unit 3 - Protocols and Client-Server Applications - IT
Unit 3 - Protocols and Client-Server Applications - ITUnit 3 - Protocols and Client-Server Applications - IT
Unit 3 - Protocols and Client-Server Applications - IT
 
window server 2008 mail configuration
window server 2008 mail configurationwindow server 2008 mail configuration
window server 2008 mail configuration
 
Tcpip services and applications
Tcpip services and applicationsTcpip services and applications
Tcpip services and applications
 
Mail server
Mail serverMail server
Mail server
 
E mail flow
E mail flowE mail flow
E mail flow
 
Electronic mail
Electronic mailElectronic mail
Electronic mail
 
retrieving the mail
retrieving the mailretrieving the mail
retrieving the mail
 
Application layer
Application layerApplication layer
Application layer
 
E-Mail - Technical Overview
E-Mail - Technical OverviewE-Mail - Technical Overview
E-Mail - Technical Overview
 
How Email Works
How Email WorksHow Email Works
How Email Works
 
Computer networks
Computer networksComputer networks
Computer networks
 
Email
EmailEmail
Email
 
presentation on email.pptx
presentation on email.pptxpresentation on email.pptx
presentation on email.pptx
 
Smtp, pop3, imapv 4
Smtp, pop3, imapv 4Smtp, pop3, imapv 4
Smtp, pop3, imapv 4
 
SMTP and TCP protocol
SMTP and TCP protocolSMTP and TCP protocol
SMTP and TCP protocol
 
Ch22 system administration
Ch22 system administration Ch22 system administration
Ch22 system administration
 
Clients and Servers.ppt
Clients and Servers.pptClients and Servers.ppt
Clients and Servers.ppt
 
Introduction to basics command in linux, and working in linux
Introduction to basics command in linux, and working in linuxIntroduction to basics command in linux, and working in linux
Introduction to basics command in linux, and working in linux
 

Recently uploaded

VoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBXVoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBXTarek Kalaji
 
How Accurate are Carbon Emissions Projections?
How Accurate are Carbon Emissions Projections?How Accurate are Carbon Emissions Projections?
How Accurate are Carbon Emissions Projections?IES VE
 
UiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation DevelopersUiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation DevelopersUiPathCommunity
 
Computer 10: Lesson 10 - Online Crimes and Hazards
Computer 10: Lesson 10 - Online Crimes and HazardsComputer 10: Lesson 10 - Online Crimes and Hazards
Computer 10: Lesson 10 - Online Crimes and HazardsSeth Reyes
 
Crea il tuo assistente AI con lo Stregatto (open source python framework)
Crea il tuo assistente AI con lo Stregatto (open source python framework)Crea il tuo assistente AI con lo Stregatto (open source python framework)
Crea il tuo assistente AI con lo Stregatto (open source python framework)Commit University
 
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCostKubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCostMatt Ray
 
Building AI-Driven Apps Using Semantic Kernel.pptx
Building AI-Driven Apps Using Semantic Kernel.pptxBuilding AI-Driven Apps Using Semantic Kernel.pptx
Building AI-Driven Apps Using Semantic Kernel.pptxUdaiappa Ramachandran
 
Meet the new FSP 3000 M-Flex800™
Meet the new FSP 3000 M-Flex800™Meet the new FSP 3000 M-Flex800™
Meet the new FSP 3000 M-Flex800™Adtran
 
Empowering Africa's Next Generation: The AI Leadership Blueprint
Empowering Africa's Next Generation: The AI Leadership BlueprintEmpowering Africa's Next Generation: The AI Leadership Blueprint
Empowering Africa's Next Generation: The AI Leadership BlueprintMahmoud Rabie
 
UiPath Platform: The Backend Engine Powering Your Automation - Session 1
UiPath Platform: The Backend Engine Powering Your Automation - Session 1UiPath Platform: The Backend Engine Powering Your Automation - Session 1
UiPath Platform: The Backend Engine Powering Your Automation - Session 1DianaGray10
 
COMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a WebsiteCOMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a Websitedgelyza
 
COMPUTER 10: Lesson 7 - File Storage and Online Collaboration
COMPUTER 10: Lesson 7 - File Storage and Online CollaborationCOMPUTER 10: Lesson 7 - File Storage and Online Collaboration
COMPUTER 10: Lesson 7 - File Storage and Online Collaborationbruanjhuli
 
Nanopower In Semiconductor Industry.pdf
Nanopower  In Semiconductor Industry.pdfNanopower  In Semiconductor Industry.pdf
Nanopower In Semiconductor Industry.pdfPedro Manuel
 
Videogame localization & technology_ how to enhance the power of translation.pdf
Videogame localization & technology_ how to enhance the power of translation.pdfVideogame localization & technology_ how to enhance the power of translation.pdf
Videogame localization & technology_ how to enhance the power of translation.pdfinfogdgmi
 
Salesforce Miami User Group Event - 1st Quarter 2024
Salesforce Miami User Group Event - 1st Quarter 2024Salesforce Miami User Group Event - 1st Quarter 2024
Salesforce Miami User Group Event - 1st Quarter 2024SkyPlanner
 
Designing A Time bound resource download URL
Designing A Time bound resource download URLDesigning A Time bound resource download URL
Designing A Time bound resource download URLRuncy Oommen
 
Igniting Next Level Productivity with AI-Infused Data Integration Workflows
Igniting Next Level Productivity with AI-Infused Data Integration WorkflowsIgniting Next Level Productivity with AI-Infused Data Integration Workflows
Igniting Next Level Productivity with AI-Infused Data Integration WorkflowsSafe Software
 
20230202 - Introduction to tis-py
20230202 - Introduction to tis-py20230202 - Introduction to tis-py
20230202 - Introduction to tis-pyJamie (Taka) Wang
 
Cybersecurity Workshop #1.pptx
Cybersecurity Workshop #1.pptxCybersecurity Workshop #1.pptx
Cybersecurity Workshop #1.pptxGDSC PJATK
 
Secure your environment with UiPath and CyberArk technologies - Session 1
Secure your environment with UiPath and CyberArk technologies - Session 1Secure your environment with UiPath and CyberArk technologies - Session 1
Secure your environment with UiPath and CyberArk technologies - Session 1DianaGray10
 

Recently uploaded (20)

VoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBXVoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBX
 
How Accurate are Carbon Emissions Projections?
How Accurate are Carbon Emissions Projections?How Accurate are Carbon Emissions Projections?
How Accurate are Carbon Emissions Projections?
 
UiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation DevelopersUiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation Developers
 
Computer 10: Lesson 10 - Online Crimes and Hazards
Computer 10: Lesson 10 - Online Crimes and HazardsComputer 10: Lesson 10 - Online Crimes and Hazards
Computer 10: Lesson 10 - Online Crimes and Hazards
 
Crea il tuo assistente AI con lo Stregatto (open source python framework)
Crea il tuo assistente AI con lo Stregatto (open source python framework)Crea il tuo assistente AI con lo Stregatto (open source python framework)
Crea il tuo assistente AI con lo Stregatto (open source python framework)
 
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCostKubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
KubeConEU24-Monitoring Kubernetes and Cloud Spend with OpenCost
 
Building AI-Driven Apps Using Semantic Kernel.pptx
Building AI-Driven Apps Using Semantic Kernel.pptxBuilding AI-Driven Apps Using Semantic Kernel.pptx
Building AI-Driven Apps Using Semantic Kernel.pptx
 
Meet the new FSP 3000 M-Flex800™
Meet the new FSP 3000 M-Flex800™Meet the new FSP 3000 M-Flex800™
Meet the new FSP 3000 M-Flex800™
 
Empowering Africa's Next Generation: The AI Leadership Blueprint
Empowering Africa's Next Generation: The AI Leadership BlueprintEmpowering Africa's Next Generation: The AI Leadership Blueprint
Empowering Africa's Next Generation: The AI Leadership Blueprint
 
UiPath Platform: The Backend Engine Powering Your Automation - Session 1
UiPath Platform: The Backend Engine Powering Your Automation - Session 1UiPath Platform: The Backend Engine Powering Your Automation - Session 1
UiPath Platform: The Backend Engine Powering Your Automation - Session 1
 
COMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a WebsiteCOMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a Website
 
COMPUTER 10: Lesson 7 - File Storage and Online Collaboration
COMPUTER 10: Lesson 7 - File Storage and Online CollaborationCOMPUTER 10: Lesson 7 - File Storage and Online Collaboration
COMPUTER 10: Lesson 7 - File Storage and Online Collaboration
 
Nanopower In Semiconductor Industry.pdf
Nanopower  In Semiconductor Industry.pdfNanopower  In Semiconductor Industry.pdf
Nanopower In Semiconductor Industry.pdf
 
Videogame localization & technology_ how to enhance the power of translation.pdf
Videogame localization & technology_ how to enhance the power of translation.pdfVideogame localization & technology_ how to enhance the power of translation.pdf
Videogame localization & technology_ how to enhance the power of translation.pdf
 
Salesforce Miami User Group Event - 1st Quarter 2024
Salesforce Miami User Group Event - 1st Quarter 2024Salesforce Miami User Group Event - 1st Quarter 2024
Salesforce Miami User Group Event - 1st Quarter 2024
 
Designing A Time bound resource download URL
Designing A Time bound resource download URLDesigning A Time bound resource download URL
Designing A Time bound resource download URL
 
Igniting Next Level Productivity with AI-Infused Data Integration Workflows
Igniting Next Level Productivity with AI-Infused Data Integration WorkflowsIgniting Next Level Productivity with AI-Infused Data Integration Workflows
Igniting Next Level Productivity with AI-Infused Data Integration Workflows
 
20230202 - Introduction to tis-py
20230202 - Introduction to tis-py20230202 - Introduction to tis-py
20230202 - Introduction to tis-py
 
Cybersecurity Workshop #1.pptx
Cybersecurity Workshop #1.pptxCybersecurity Workshop #1.pptx
Cybersecurity Workshop #1.pptx
 
Secure your environment with UiPath and CyberArk technologies - Session 1
Secure your environment with UiPath and CyberArk technologies - Session 1Secure your environment with UiPath and CyberArk technologies - Session 1
Secure your environment with UiPath and CyberArk technologies - Session 1
 

Simple mail transfer protocol

  • 2. Overview • Introduction to SMTP • History of Smtp • General features of SMTP • Sendmail • Relays And Gate ways • How SMTP works • Limitations in SMTP • Example of SMTP
  • 3. 3
  • 4. 4 Composes, reads, replies to ,forwards and handles mailboxes Transfers mails from one host to another Collects mail and delivers to user agent Transfers mails from one host to another Collects mail and delivers to user agentIntroduction…
  • 5. Introduction to SMTP • SMTP is an Internet standard for electronic mail. • SMTP is the protocol in widespread use today. • It is the actual protocol used to transfer mail from MTA to MTA. • MTA: Mail Transfer Agent .... A program that actually routes and delivers mail. • MUA: Mail User Agen t ... A program that is used to access mail after delivery. • The objective of SMTP is to transfer mail reliably and efficiently.
  • 6. History of SMTP • The SMTP specification originally started with the Mail Transfer Protocol in 1980 • It evolved into Simple Mail Transfer Protocol (SMTP) in 1981 • Specified in RFC 821 • Most recent RFC is 2821 • First and most important implementation is sendmail
  • 7. General Features • Independent of underlying transmission subsystem. • Just needs a reliable ordered data stream channel. • Operates over TCP port 25. • Uses an request-response protocol that is useful to human readers (SMTP commands). • SMTP sessions are stateful, with both parties carefully maintaining a common view of the current state.
  • 8. 8 Sendmail Mail Transfer Agent [MTA] : is a computer program or software agent that transfers electronic mail messages from one computer to another. • Sendmail is a MTA • Supports several mail transfers including SMTP • Pro’s • Can perform header rewriting, mail routing • Extensive support available • Con’s • Not secure • Code is bulky [compared to other MTA’s such as qmail]
  • 10. 10 • SMTP server can also assume the role of a “relay” • SMTP mail gateways are used to transport mail prepared by a protocol other than SMTP Relays and Gateways SMTP supported Non-SMTP supported
  • 11. 11 Link Layer PCI IP-PCI Keyword: argument(s) Command format: Response format: 3-digit status code [textual information] How SMTP works? Link Layer PCI IP-PCI TCP-PCI SMTP command/responseTCP-PCI SMTP command/responseTCP-PCI SMTP command/response
  • 12. 12 How SMTP works : Status Codes The Server responds with a 3 digit code that may be followed by text info – 2## - Success – 3## - Command can be accepted with more information – 4## - Command was rejected, but error condition is temporary – 5## - Command rejected, Bad User!
  • 13. 13 Limitations in SMTP • Only uses NVT 7 bit ASCII format – How to represent other data types? • Susceptible to misuse (Spamming, faking sender address)