freeswitch as a microservice
TRANSCRIPT
FreeSWITCH as a Microservice
vs.
What we are: an MVNO/MVNE running on the Sprint Network
What we do: rapid development cycles and constant iteration to be a different kind of consumer cellular company.
Quickly: What is a microservices architecture?
Quickly: What is a microservices architecture?
• Monolithic• Simpler architecture• Generally confined to a single language
or framework • Scaling Inefficient• Depth of Knowledge Required (DOKR)
can lead to substantially increased technical debt
• Microservices• More complex• Decoupled services allow for more rapid
development • Increased scalability and fault tolerance• Knowledge need not span multiple services • Deployment is more complex but… simpler?
That Brings Us To…
Doesn’t Live in A Bubble
Doesn’t Live in A Bubble• Billing • Fraud Management • Call Tracking & Analytics • Performance Monitoring • Call Quality Analysis • Failover • Realtime Multimodal Interaction (PSTN->WebRTC…)
Very different domains requiring very different processing backends, language requirements, and service architectures
Simple ExampleUser Registration: mod_xml_curl
• Queries a remote API for registration information • API uses business logic to decide which registrations
permissions to bestow
<binding name="directory"><param name="gateway-url" value="https://dev.ringplus.net/endpoints" bindings="directory"/><param name="gateway-credentials" value="journey:foreigner" /><param name="auth-scheme" value="basic"/>
</binding>
Works for dialplan, configuration, and phrases Decouples SIP endpoint information
Easy migration to a mid-registrar like Kamailio
Registration Microservice
DataStore
HTTP HTTP (XML)
??? ???
if create_sip_endpointrender :registration, status: :ok, formats: [:xml]
elserender xml: @sip_endpoint.errors, status: :unprocessable_entity
end
XML
RUBY
How About Something More Fun
Here’s a little something.Setting Preprocessor values: exec-set
<X-PRE-PROCESS cmd="exec-set" data="local_ip_v4 = ip addr show eth0 | awk '/inet /{print $2}' | head -n 1 | cut -d '/' -f 1"/>
Scenario: You’re starting a container and don’t know the IP
<X-PRE-PROCESS cmd="exec-set" data="internal_sip_port = echo $INTERNAL_SIP_PORT"/>
Scenario: You’re big into 12-Factor and are using lots of ENV variables
<X-PRE-PROCESS cmd="exec-set" data="rtp_start_port = /etc/freeswitch/rtp_ports_based_on_env
Scenario: It’s complicated, man. I need some real logic processing.
Go routine that queries a service to retrieve the public RTP ports for this container. That service also opens/maps firewall and NAT ports correctly, or can really do anything.
Talking To FreeSWITCH Is Easy
Many choices of built-in modules and 3rd party libraries
• Ruby: Adhearsion (https://github.com/adhearsion/adhearsion) • JavaScript: https://github.com/shimaore/esl • Go: https://github.com/0x19/goesl • Python: Python ESL • mod_xml_rpc • mod_verto • etc…
What About Push?
This Sounds Complex. Can we make this easier?
Let’s Talk About One Way To Go
• You may have heard me talk about this last year. I’m still talking about it.• Containers should be single-process, no durable storage, ephemeral little
creatures• Lightweight and distributable containers• Scalability due to built in resilience and orchestration layers• Higher packing density than virtual machines due to shared libs
Docker
DOCKER NETWORKING….
IT’S GOTTEN BETTER!
Docker Networking
• Docker 1.12 (June) allows for easy, multi-host VXLAN routing• Easily scale containers across nodes • Built in state reconciliation for resilient deployments• Orchestration is built into Docker Engine
• Includes auto-load balancing of inbound requests to multiple containers utilizing in-kernel Linux IPVS, automatic TLS generation, and a free basket of kittens
Note: Docker is still a moving target.
• Documentation• Best Practices• Service Integration/Discovery
Practical Use Case
Scaling The Business LogicUsing Adhearsion for your dialplan.
- We use it for ease and rapidity of development - Can leverage the Ruby ecosystem for gems
Problem: Ruby MRI is locked to a single CPU, so can become CPU bound Solution: JRuby(?)
Problem Redux: Call volume on a particular node is exceeding CPU capacity due to amazingly wonderful consumer adoption (Pokémon Go Syndrome) Solution: Scale nodes
• FreeSWITCH is rarely the blocker but can consume enough CPU to max out • Adhearsion communicates with mod_rayo via XMPP - many clients, one server.
CPU BOUNDSave money on the weekends ya’ll!
Scaling The Business LogicUsing Adhearsion for your dialplan.
- We use it for ease and rapidity of development - Can leverage the Ruby ecosystem for gems
Problem: Ruby MRI is locked to a single CPU, so can become CPU bound Solution: JRuby
Problem Redux: Call volume on a particular node is exceeding CPU capacity due to amazingly wonderful consumer adoption (Pokémon Go Syndrome) Solution: Scale nodes
• FreeSWITCH is rarely the blocker but can consume enough CPU to max out • Adhearsion communicates with mod_rayo via XMPP - many clients, one server.
root@adhearsion-swarm-01:~# docker service lsID NAME REPLICAS IMAGE COMMANDec23ck911hgc adhearsion 20/20 ringplus/adhearsion:latest28ght39gvfce freeswitch 1/1 ringplus/freeswitch_v1.6:latest
root@adhearsion-swarm-01:~# docker service scale adhearsion=20adhesion scaled to 20
FreeSWITCH
Adhearsion
NYC Datacenter
Adhearsion + FreeSWITCH
Spike Condition with DockerAdhearsion
DigitalOcean NYC-1
NYC Datacenter
Kamailio
• Host monitoring detects low-CPU condition on Node 1 • collectd container • Active call monitoring
• Calls Ansible to spin up a new DO container • Adhearsion images pulled from Docker repo • Start containers with overlay network and information on parent
FS container
• Quiesce Adhearsion on affected system • Gracefully shutdown
• Update Kamailio MySQL DB with new dispatcher information if FreeSWITCH scaling is necessary.
FreeSWITCH Joins A Bunch of Microservices
FreeSWITCH
Static Assets Voicemails
IVR
AdhearsionKafkaELK
S3 / Gluster
Fraud API Kafka Consumer
Billing API
Redis
Logs WAL-E Backups
Postgres
HTTP/S, HTTPS, XMPP, XML, Go, Ruby, Elixer
RBT Selection API
User API
NO MAGIC PILL YET.
STILL REQUIRES DEV, OPS, DEVOPS, MANAGEMENT
COMPLEXITY
Finals Thoughts & Bon Mots
• If you can help it, don’t start with microservices unless you have a team willing and able. • Do build your monolithic app with an eye toward breaking it apart.
• Consider that you’ll eventually need to scale one part, but not others.• Follow a Services or Operations pattern to development - make them as independent
as possible to facilitate eventual decoupling.
• Do think of your FreeSWITCH and VoIP infrastructure as smaller services.• Consider your business case: Instead of running one 10k channel FreeSWITCH, why not
run 100 100-channel FreeSWITCH instances?
