Complete Guide to ASN Registration: Requirements, Process & Best Practices

An Autonomous System Number (ASN) is essential infrastructure for any organization operating its own network with independent routing policies. Whether you're an Internet Service Provider (ISP), hosting provider, enterprise with multi-homed connectivity, or content delivery network, obtaining an ASN is a critical step in establishing your presence on the global Internet.

This comprehensive guide walks you through everything you need to know about ASN registration: from understanding eligibility requirements across different Regional Internet Registries (RIRs) to preparing your application, navigating the approval process, and implementing your newly assigned ASN.

What is an Autonomous System Number?

An Autonomous System Number (ASN) is a globally unique identifier assigned to an autonomous system (AS) for use in Border Gateway Protocol (BGP) routing. An autonomous system represents a collection of IP networks and routers under the control of a single organization that presents a common routing policy to the Internet.

ASNs are defined in RFC 4271 and RFC 6793. Originally, ASNs were 16-bit numbers (ranging from 1 to 65,535), but due to depletion concerns, the system expanded to 32-bit ASNs, providing over 4.2 billion possible numbers (0 to 4,294,967,295).

Public vs Private ASNs

Similar to IP address space, ASNs are divided into public and private ranges:

Public ASNs: Globally unique numbers assigned by RIRs, required for Internet routing
Private ASNs: Reserved for internal use only, not announced on the public Internet
- 16-bit range: 64,512 to 65,534
- 32-bit range: 4,200,000,000 to 4,294,967,294

As specified in RFC 6996, private ASNs should never appear in the public Internet routing table.

Why Do You Need an ASN?

Organizations typically need an ASN in the following scenarios:

Multi-homing Configuration

The most common justification for an ASN is multi-homing: connecting to two or more upstream Internet Service Providers (ISPs) simultaneously. Multi-homing provides:

Redundancy: If one ISP connection fails, traffic automatically routes through other connections
Load balancing: Distribute traffic across multiple connections for optimal performance
Provider independence: Avoid vendor lock-in by maintaining relationships with multiple ISPs
Route control: Implement custom routing policies based on cost, performance, or policy requirements

Unique Routing Policy

Even without multi-homing, organizations may need an ASN if they have:

Complex traffic engineering requirements
Need to implement specific routing policies
Peering relationships with other autonomous systems
Content delivery or caching infrastructure requiring BGP routing

Business Requirements

From a business perspective, having your own ASN demonstrates:

Professional network operations capability
Commitment to network infrastructure investment
Independence from service provider routing decisions
Credibility when establishing peering relationships

Regional Internet Registry (RIR) Overview

ASNs are allocated and managed by five Regional Internet Registries (RIRs), each serving specific geographic regions:

RIPE NCC (Europe, Middle East, Central Asia)

RIPE NCC serves Europe, the Middle East, and parts of Central Asia. RIPE is known for its transparent policy development process and active community involvement.

Service region: Europe, Middle East, parts of Central Asia

ARIN (North America)

American Registry for Internet Numbers (ARIN) serves the United States, Canada, and portions of the Caribbean.

Service region: United States, Canada, Caribbean islands

APNIC (Asia-Pacific)

Asia-Pacific Network Information Centre (APNIC) covers the Asia-Pacific region, including National Internet Registries (NIRs) in countries like Japan, South Korea, and China.

Service region: Asia-Pacific region

LACNIC (Latin America and Caribbean)

Latin America and Caribbean Network Information Centre (LACNIC) serves Latin America and parts of the Caribbean.

Service region: Latin America, Caribbean

AFRINIC (Africa)

African Network Information Centre (AFRINIC) provides registry services for the African continent.

Service region: Africa

The RIR you work with depends on your organization's physical location and where your network infrastructure operates. This guide covers requirements and processes for all five RIRs.

ASN Registration Requirements by RIR

Each RIR has specific eligibility criteria and technical requirements for ASN registration. Understanding these requirements before beginning your application ensures a smooth process.

RIPE NCC Requirements

To obtain an ASN from RIPE NCC, you must:

Technical Requirements:

Demonstrate multi-homing with at least two different upstream providers
Provide the ASNs and contact information for both upstream providers
Hold a minimum IP address allocation (/24 IPv4 or /48 IPv6)
Have a documented routing policy

Organizational Requirements:

Be a RIPE NCC member (Local Internet Registry - LIR) or work through a sponsoring LIR
Maintain valid contact information in the RIPE Database
Sign the RIPE NCC Standard Service Agreement (for direct members)

Important Update (2025): RIPE NCC is currently reviewing policy proposal 2025-01 "ASN assignment criteria revisited", which would simplify requirements. Under the proposed policy, LIRs and End Users may request a single ASN without justification, with additional ASNs requiring demonstration of unique routing policies.

Current Practice: As of 2025, RIPE requires multi-homing justification, though enforcement has become more flexible as the community recognizes that ASNs are no longer a scarce resource with the adoption of 32-bit ASN space.

ARIN Requirements

ARIN has streamlined its ASN request process significantly in recent years. Current requirements include:

Organizational Requirements:

Be a legally formed business entity, nonprofit corporation, or government entity
Operate within the ARIN service region
Have an ARIN Online account with valid Point of Contact (POC) records
Have a valid Organization Identifier (Org ID)

Technical Requirements:

Provide names and ASNs of two upstream ISPs for multi-homing, OR
Describe a unique routing policy that requires an ASN

Simplified Documentation: According to ARIN's ASN request guidelines, no copies of contracts or invoices are required. The previous 30-day usage requirement has been lifted, though ARIN still requires a projected date of usage.

Key Advantage: ARIN accepts either multi-homing OR unique routing policy as justification, providing more flexibility than some other RIRs.

APNIC Requirements

APNIC follows RFC 1930 guidelines and requires:

Eligibility Criteria:

Network is currently multihomed, OR
Need to interconnect with other autonomous systems, OR
Can demonstrate you will meet these criteria within a reasonably short time after receiving an ASN

Application Options:

Apply directly to APNIC as a member or non-member
Apply through your National Internet Registry (NIR) if applicable
Request through a sponsoring LIR

Documentation Requirements:

Detailed routing policy specification
ASNs with which you will interconnect
IP addresses that will be announced through the requested ASN
Technical justification following RFC 1930 guidelines

Recent Fee Changes (2025): From January 1, 2025, each APNIC member receives two ASNs free of charge, with additional ASNs subject to an annual fee of AUD 100 and a one-time allocation fee of AUD 500. Source: APNIC

LACNIC Requirements

LACNIC's ASN allocation policy requires:

Technical Requirements:

Require interconnection with other independent autonomous systems at time of application, OR
Plan to establish such interconnection within six months

Documentation Requirements:

Detailed routing policy
ASNs with which the organization will interconnect
IP addresses to be announced through the requested ASN
Technical justification demonstrating need for globally unique ASN

Policy Flexibility: LACNIC does not strictly require multi-homing, accepting plans for future interconnection within six months as valid justification. Source: LACNIC Policy Manual

AFRINIC Requirements

AFRINIC's requirements are defined in their Consolidated Policy Manual:

Eligibility Criteria:

Be an AFRINIC resource member, AND
Interconnect (including peering) with more than one AS, OR
Show a unique routing policy, OR
Demonstrate technical need for globally unique ASN

Future Planning: Organizations may qualify if they demonstrate they will meet criteria within six months of receiving the ASN.

Resource Philosophy: AFRINIC emphasizes that ASNs are public resources distributed based on demonstrated need. Assignment does not confer ownership; organizations are custodians without the right to sell or transfer ASNs except in cases of mergers, acquisitions, or business reorganization.

Fee Advantage: AFRINIC LIRs are not charged annual maintenance fees for ASNs.

Step-by-Step ASN Registration Process

The ASN registration process varies slightly by RIR, but follows a general pattern. This section provides a comprehensive walkthrough.

Step 1: Determine Your RIR

Your RIR is determined by your organization's geographic location and where you operate your network infrastructure. Use these guidelines:

Headquartered in Europe/Middle East/Central Asia: RIPE NCC
Headquartered in United States/Canada: ARIN
Headquartered in Asia-Pacific: APNIC (or your country's NIR)
Headquartered in Latin America: LACNIC
Headquartered in Africa: AFRINIC

If your organization operates in multiple regions, your primary RIR is typically where your headquarters and main operations are located.

Step 2: Establish RIR Membership or Sponsorship

Direct Membership Option:

Most RIRs allow direct membership, giving you full control over your resources:

RIPE NCC: Become a Local Internet Registry (LIR) member (€1,400 annual fee)
ARIN: No membership required; pay per-resource fees ($250/year for ASN + Registration Services Plan)
APNIC: Member or non-member registration available (fees vary by resource holdings)
LACNIC: Membership required for resource requests
AFRINIC: Resource member status required

Sponsoring LIR Option:

If you don't want to become a direct RIR member, you can work through a sponsoring LIR (also called Provider Independent or PI sponsorship):

Sponsoring LIR handles the registration on your behalf
You pay the LIR a service fee (typically €50-€500 annually)
LIR maintains the assignment in the RIR database
You remain the user of the ASN with rights to use it

Many organizations choose sponsorship to avoid the administrative overhead and higher costs of direct RIR membership, especially if they only need one ASN and small IP allocations.

Step 3: Gather Required Documentation

Before starting your application, compile the following information:

Technical Documentation:

Routing Policy Documentation
- Description of your routing strategy
- Traffic engineering plans
- BGP community usage
- Route filtering policies
Multi-homing Information (if applicable)
- Names and ASNs of upstream providers
- Contact information (email addresses) for upstream provider NOC
- Letter of intent or service agreement from each provider
- IP addresses of BGP peering sessions
IP Address Resources
- Current IP allocations (/24 IPv4 minimum or /48 IPv6)
- Plans for announcing these prefixes
- Assignment documentation from your RIR

Organizational Documentation:

Business Registration
- Proof of legal entity formation
- Business registration number
- Operating jurisdiction
Contact Information
- Administrative contact details
- Technical contact details
- Abuse contact (required by most RIRs)
- Organization address and phone
Network Infrastructure Details
- Description of your network
- Geographic scope
- Services provided
- Number of customers (if applicable)

Step 4: Prepare Your Justification

Your ASN justification is the most critical part of your application. It must clearly demonstrate why you need a globally unique ASN.

Strong Justification Examples:

Example 1: Multi-homed ISP

Our organization operates a regional ISP providing Internet connectivity to
enterprise customers. We currently maintain transit agreements with [ISP A]
(AS64500) and [ISP B] (AS64501) for redundancy and load balancing. We hold
IPv4 allocation 198.51.100.0/24 and IPv6 allocation 2001:db8::/48, which
we will announce via BGP to both upstream providers. An ASN is required to
implement our multi-homing strategy and ensure service continuity.

Example 2: Unique Routing Policy

Our content delivery network operates cache servers in 15 locations across
Europe. We require an ASN to implement anycast routing and optimize content
delivery based on geographic proximity. Our routing policy includes selective
prefix announcements to different peers based on geographic location and
traffic engineering requirements that cannot be achieved through provider-
assigned addressing.

Example 3: Enterprise Multi-homing

Our organization requires highly available Internet connectivity for business-
critical applications. We have established service agreements with [ISP A]
(AS64500) and [ISP B] (AS64501) to provide redundant Internet access. We hold
Provider Independent IPv4 space 203.0.113.0/24 which we need to announce to
both providers with equal preference. An ASN is necessary to implement BGP
multi-homing and ensure automatic failover.

Weak Justifications to Avoid:

"We want to learn BGP" (use private ASNs for testing)
"Future plans" without concrete timeline or agreements
"We might need multi-homing someday" (apply when ready)
Single-homed networks without unique routing policy justification

Step 5: Submit Your Application

Each RIR has a specific application process:

RIPE NCC:

Log into the RIPE NCC LIR Portal
Navigate to Request New Resources > Request ASN
Complete the online form with technical justification
Provide upstream provider ASNs and contact details
Submit for evaluation

Processing time: Typically 1-3 business days for straightforward requests

ARIN:

Log into ARIN Online
Navigate to Actions > Request Resources > Request ASN
Complete the request form including routing policy or multi-homing details
Submit for evaluation
If approved, receive invoice and Registration Services Agreement (if applicable)
Return signed RSA and payment

Processing time: Typically 3-7 business days

APNIC:

Log into MyAPNIC
Navigate to Resources > Request Resources
Select ASN request type
Complete application with detailed routing policy
Submit for evaluation

Processing time: Typically 5-10 business days

LACNIC:

Access the LACNIC resource request system
Complete the ASN request form
Provide detailed interconnection information
Submit supporting documentation

Processing time: Typically 5-15 business days

AFRINIC:

Log into the AFRINIC Member Portal
Submit ASN request with justification
Provide technical documentation

Processing time: Typically 7-14 business days

Step 6: RIR Evaluation and Follow-up

After submission, RIRs evaluate your request:

Evaluation Process:

Technical review of justification
Verification of upstream provider information (for multi-homing)
Validation of IP address holdings
Completeness check of documentation

Possible Outcomes:

Approved: ASN assigned, invoice issued (if applicable)
Additional Information Required: Hostmaster contacts you for clarification
Rejected: Application denied with explanation of deficiencies

Common Reasons for Additional Information Requests:

Unclear routing policy justification
Unable to verify upstream provider information
Insufficient IP address resources
Missing organizational documentation

Response Time Critical: If the RIR requests additional information, respond promptly (within 7 days) to avoid application closure.

Step 7: Payment and Finalization

Once approved:

RIPE NCC:

If you're an LIR, ASN is included in annual membership fee
For PI assignments through sponsoring LIR, €50 annual fee (paid to LIR)
ASN becomes active immediately after approval

ARIN:

Invoice issued for $250 annual fee plus Registration Services Plan
Sign and return RSA if required
ASN becomes active after payment receipt

APNIC:

Invoice for allocation fee (AUD 500) if exceeding free ASN allocation
Annual fee (AUD 100) for additional ASNs
Sign-up fee (AUD 500) for new members

LACNIC & AFRINIC:

Fees typically included in membership costs
Some additional fees may apply for specific resource types

Step 8: Configure Your Routing

After receiving your ASN, you can begin BGP configuration:

Essential Configuration Steps:

Create Route Objects in IRR databases (RIPE, RADB, etc.)
Register BGP peering sessions with upstream providers
Configure BGP on your routers with your new ASN
Implement route filtering policies
Set up monitoring for BGP sessions and route propagation
Test failover scenarios before going into production

Coordination with Upstream Providers:

Provide your ASN to upstream providers in advance
Coordinate BGP session turn-up timing
Configure initial prefix announcements
Test reachability before announcing widely

ASN Registration Costs

Understanding the full cost of ASN registration helps with budget planning:

Initial Registration Costs

RIPE NCC:

LIR membership: €1,400 first year (includes ASN)
Through sponsoring LIR: €50-€200 setup fee (varies by provider)

ARIN:

No separate registration fee
$250 annual maintenance included in first invoice

APNIC:

Sign-up fee: AUD 500 (for new members)
Allocation fee: AUD 500 (for ASNs beyond free allocation)

LACNIC:

Varies by membership category
Generally included in membership fees

AFRINIC:

Included in resource member fees
No separate ASN charges

Annual Maintenance Costs

RIPE NCC:

LIR: €1,400 per year (flat rate regardless of resource holdings)
Through sponsoring LIR: €50-€100 per year (varies by provider)
Note: New 2025 proposal may introduce €50 per ASN fee

ARIN:

$250 per year (flat rate for all ASN holders)
Includes Registration Services Plan

APNIC:

First two ASNs: Free
Additional ASNs: AUD 100 per year each
Plus annual membership fees based on resource holdings

LACNIC:

Included in membership fees
Fees vary by membership category

AFRINIC:

No annual ASN maintenance fees for LIRs

Hidden Costs to Consider

Beyond RIR fees, budget for:

Transit Costs: $500-$5,000+ monthly per provider (two minimum for multi-homing)
Hardware: BGP-capable routers ($2,000-$50,000+ depending on capacity)
Staff Training: BGP and routing protocol expertise
Monitoring Tools: BGP monitoring and alerting systems
Peering Facility Costs: If establishing peering relationships (colocation, cross-connects)

Common ASN Registration Issues and Solutions

Issue 1: Upstream Provider Verification Fails

Symptoms: RIR cannot verify your upstream provider information or providers don't respond to verification requests.

Cause: Incorrect contact information, provider NOC not aware of your request, or provider doesn't support BGP for your service tier.

Solution:

Coordinate with your upstream providers BEFORE submitting ASN request
Ensure providers are aware they may receive verification emails from the RIR
Provide accurate NOC email addresses (not sales contacts)
Confirm your service agreement includes BGP support
Consider upgrading service tier if current plan doesn't support BGP

Issue 2: Insufficient IP Address Justification

Symptoms: RIR requests documentation for IP address holdings or states you don't meet minimum allocation requirements.

Cause: No documented IP allocations or allocations smaller than minimum requirements (/24 IPv4 or /48 IPv6).

Solution:

Obtain Provider Independent (PI) IP space before applying for ASN
Document existing Provider Aggregatable (PA) space if provider supports BGP announcements
Apply for IPv6 /48 allocation if IPv4 space is unavailable
Request IP space and ASN simultaneously if eligible

Issue 3: Weak Technical Justification

Symptoms: RIR rejects application or requests additional technical details about routing policy.

Cause: Vague or insufficient explanation of why you need an ASN.

Solution:

Provide specific technical details about multi-homing configuration
Document unique routing requirements that require an ASN
Include concrete examples of routing policies you'll implement
Reference specific BGP features you'll use (communities, AS-PATH prepending, etc.)
Avoid generic statements; be specific about your network architecture

Issue 4: Single-homing Without Unique Policy

Symptoms: Application rejected because you only have one upstream provider.

Cause: Most RIRs require multi-homing or demonstration of unique routing policy.

Solution:

Establish a second upstream provider relationship before applying
Document a genuinely unique routing policy if single-homed
Consider if you actually need an ASN (many single-homed networks don't)
Use provider-assigned resources if only single-homed

Issue 5: Organizational Documentation Issues

Symptoms: RIR cannot verify your organization's legal status or contact information.

Cause: Incomplete registration, outdated contact information, or inability to verify business entity.

Solution:

Ensure all POC records are complete and current
Update organization details in RIR database before requesting ASN
Provide business registration documents if requested
Verify email addresses work and are monitored regularly

Best Practices for ASN Management

Maintain Accurate Registry Data

Update contact information immediately when changes occur
Respond to RIR validation requests promptly (typically annual)
Keep abuse contact functional and monitored 24/7
Document changes to routing policy in registry databases

Implement Robust BGP Security

RPKI (Resource Public Key Infrastructure)
- Create ROAs (Route Origin Authorizations) for all prefixes
- Validate routes received from peers
- Prevents route hijacking and improves routing security
IRR (Internet Routing Registry) Objects
- Create and maintain route objects
- Register aut-num objects with routing policy
- Keep routing policy documentation current
BGP Filtering
- Implement strict prefix filtering on customer and peer sessions
- Use BGP communities for traffic engineering
- Filter private ASNs, bogon prefixes, and invalid routes
Monitoring and Alerting
- Monitor BGP session status continuously
- Set up alerts for route flapping or session failures
- Use BGP looking glass services to verify global visibility
- Monitor route propagation across multiple vantage points

Plan for Growth

Design scalable routing architecture from the start
Document your network topology and routing policies
Consider future peering relationships when designing AS policies
Reserve budget for additional transit or peering as network grows

Establish Peering Relationships

Once you have an ASN and established routing:

Identify potential peering partners at Internet Exchange Points (IXPs)
Join IXPs in strategic locations
Register with PeeringDB to facilitate peering coordination
Develop a peering policy (open, selective, or restrictive)
Document technical requirements for peering partners

Using Via-Registry Services for ASN Registration

ASN registration can be complex, especially for organizations new to BGP and Internet routing. Via-Registry.com simplifies this process:

What We Offer

Complete ASN registration services for all five RIRs
Application preparation and submission with expert guidance
Justification documentation development
Upstream provider coordination assistance
Sponsoring LIR services for RIPE region (no direct RIPE membership required)
Ongoing ASN maintenance and registry management
Technical consultation for BGP implementation

Benefits of Professional ASN Registration

Higher approval rates through properly prepared applications
Faster processing with complete documentation from the start
Expert guidance on complex technical requirements
Ongoing support for registry maintenance and updates
Cost optimization through efficient resource planning

Get started with our ASN Registration Service to simplify this process and ensure successful ASN acquisition.

Frequently Asked Questions

How long does ASN registration take?

ASN registration timelines vary by RIR:

RIPE NCC: 1-3 business days for straightforward applications
ARIN: 3-7 business days
APNIC: 5-10 business days
LACNIC: 5-15 business days
AFRINIC: 7-14 business days

Additional time required if the RIR requests supplementary information or documentation. Allow 2-4 weeks total from initial application to receiving your ASN, including time for upstream provider coordination.

Can I transfer my ASN to another organization?

ASN transfers are generally not permitted except in specific circumstances:

Mergers and acquisitions: ASN can transfer as part of legitimate business combination
Business reorganization: Transfers allowed for corporate restructuring
Geographic relocation: May require ASN transfer between RIRs (complex process)

The specific RIR from which you received the ASN determines transfer policies. Some RIRs have established inter-RIR transfer policies; others prohibit transfers entirely.

Unlike IPv4 addresses, ASNs generally cannot be sold or traded on the open market, as they're considered public resources assigned based on operational need rather than property rights.

Do I need my own IP addresses to get an ASN?

Not always, but usually:

RIPE NCC: Requires minimum /24 IPv4 or /48 IPv6 allocation ARIN: Doesn't explicitly require IP addresses but ASN isn't useful without them APNIC: Requires IP addresses you intend to announce LACNIC: Requires documentation of IP addresses for announcement AFRINIC: Typically requires IP allocation

Practical reality: An ASN is useless without IP addresses to announce via BGP. Most organizations obtain Provider Independent (PI) IP space before or simultaneously with their ASN request. Some RIRs allow concurrent applications for both ASN and PI space.

Can I use a private ASN instead?

Private ASNs (64,512-65,534 and 4,200,000,000-4,294,967,294) are suitable for:

Testing and lab environments
BGP configurations that don't reach the Internet
Internal MPLS or VPN routing

Private ASNs should NEVER be used for:

Internet routing (will be filtered by most ISPs)
Multi-homing to the Internet
Any configuration where your ASN appears in public routing tables

If you need to route on the public Internet, you need a public ASN assigned by an RIR.

What happens if my ASN registration is rejected?

If your ASN application is rejected:

Review the rejection reason carefully
Address the specific deficiencies identified by the RIR
Gather additional documentation if needed
Resubmit the application once issues are resolved

Common rejection reasons include:

Insufficient technical justification
Cannot verify upstream providers
Missing organizational documentation
Not meeting minimum requirements for multi-homing

Most rejections can be overcome by providing additional information or adjusting your network architecture to meet requirements. RIR hostmasters often provide specific guidance on what's needed for approval.

Can I register an ASN in multiple RIRs?

No. ASNs are globally unique and assigned by only one RIR. However:

Your network may operate in multiple regions while using a single ASN
Inter-RIR transfers may be possible if your organization relocates
Some organizations hold multiple ASNs from different RIRs for separate business units

If you operate a global network, you typically register your ASN with the RIR in your headquarters region and use that ASN worldwide. Your ASN works globally regardless of which RIR assigned it.

Summary

ASN registration is a critical milestone for organizations operating independent network infrastructure. Success requires:

Understanding RIR-specific requirements and choosing the appropriate registry
Preparing comprehensive technical justification demonstrating need for globally unique ASN
Gathering complete documentation including upstream provider information and routing policies
Budgeting appropriately for both RIR fees and operational costs
Implementing BGP security best practices including RPKI and IRR maintenance
Maintaining accurate registry data and responding to RIR communications promptly

With proper planning and preparation, ASN registration is a straightforward process that opens opportunities for improved network resilience, routing control, and Internet infrastructure independence.

Next Steps

Now that you understand the ASN registration process, explore these related topics:

Learn the fundamentals: Read our guide on What is an ASN? How BGP Routing Works
Compare RIR policies: Review ASN Registration Requirements by RIR
Understand costs: See our Cost Breakdown: ASN Registration Fees
Prepare your application: Follow our guide How to Prepare Your ASN Justification
Explore use cases: Discover ASN Use Cases and Real-World Examples