Blog
The ZafeConnect blog
Practical articles on business messaging: how an SMS reaches a phone, how to protect one-time codes, how to handle consent, and how to compare providers. Written for people who send messages at scale.
Basics
How messages are built, addressed and sent.
How an SMS gets from your application to a phone
Follow one A2P SMS from your application to the handset: the API call, routing, the operator network, delivery and the report that comes back.
Read the article Basics · 5 min readWhy one SMS can count as two: GSM-7, Unicode and segments
Why one SMS can count as two or three: the 160 and 70 character limits, how emoji and curly quotes change encoding, and how to keep messages cheap.
Read the article Basics · 5 min readAlphanumeric sender ID, long number or short code?
Alphanumeric sender ID, long number or short code: what each is, what it can and cannot do, and how to choose for one-way alerts or two-way conversations.
Read the article Basics · 4 min readPhone numbers in E.164: format and validate before you send
How to store and validate phone numbers for messaging: the E.164 format, country codes, leading zeros, and why a number check before sending saves money.
Read the articleDelivery and routing
What happens between your system and the handset, and how to read the result.
Delivery receipts explained: what “delivered” really means
What “delivered” means in an SMS delivery report, the other statuses you will see, why some destinations return less detail, and how to use the data.
Read the article Delivery and routing · 5 min readFailover routing: what happens when a route fails
What failover routing is, how a provider detects a failing route, how it differs from channel fallback, and how to avoid duplicate one-time codes.
Read the article Delivery and routing · 6 min readHow to judge international SMS routes
How to judge international SMS routes: direct connections and aggregators, grey routes, sender names by country, price and quality, Asia, the US and failover.
Read the article Delivery and routing · 5 min readSending SMS at scale: how to plan for Black Friday, payday and alarms
How to send millions of SMS without delays: throughput, queues, prioritisation, throttling, load tests and what to tell your provider before a peak.
Read the article Delivery and routing · 5 min readSMS KPIs: what to follow and how to monitor delivery in real time
Which numbers to follow when you send SMS, how to monitor delivery in real time with webhooks and dashboards, and what to set alerts on.
Read the article Delivery and routing · 6 min readMessaging in the Nordic countries from Denmark: differences and a checklist
What typically differs when you message Sweden, Norway, Finland and Iceland from Denmark: numbers, senders, characters, consent, plus a checklist.
Read the articleSecurity and sign-in
One-time codes, second factors and fraud that targets them.
One-time code messages that work
How to write and send one-time code messages that people use and attackers cannot exploit: wording, length, expiry, resend limits and the auto-fill format.
Read the article Security and sign-in · 5 min readSMS codes, authenticator apps or passkeys? Picking a second factor
Compare SMS one-time codes, authenticator apps and passkeys as a second factor: reach, security, cost and effort, and how to combine them.
Read the article Security and sign-in · 5 min readSIM swap fraud: what it is and how to reduce the risk
What SIM swap fraud is, why it threatens SMS one-time codes, the warning signs, and the controls a business can add without giving up SMS.
Read the article Security and sign-in · 6 min readSMS pumping: how to spot and stop artificially inflated traffic
What SMS pumping (artificially inflated traffic) is, the signs in your numbers, and the controls that stop it: rate limits, country rules and bot checks.
Read the articleConsent and rules
Consent, message types and data protection basics.
Consent for SMS: what a good opt-in record contains
What to store when a person agrees to receive text messages: who, when, how, what wording they saw and for which messages, and how to honour opt-outs.
Read the article Consent and rules · 5 min readTransactional or marketing? Why the line matters
The difference between transactional, service and marketing messages, why operators and regulators treat them differently, and how to handle the grey areas.
Read the article Consent and rules · 6 min readGDPR basics for teams that send messages
What GDPR means for teams that send text messages: phone numbers as personal data, lawful basis, processors, retention, transfers and data requests.
Read the article Consent and rules · 6 min readHow to assess a messaging provider’s data protection before you buy
How to assess a messaging provider’s data protection before you buy: the processing agreement, sub-processors, transfers, retention, access and incidents.
Read the articleChannels
What RCS, WhatsApp and two-way messaging add to SMS.
RCS for business: what it adds to SMS and what to plan for
What RCS business messaging adds to SMS, such as a verified sender, images and buttons, what limits it has, and why an SMS fallback still matters.
Read the article Channels · 5 min readWhatsApp Business messaging: opt-in, templates and the 24-hour window
How WhatsApp Business messaging works: opt-in, approved templates, the 24-hour customer service window, message categories and a fallback to SMS.
Read the article Channels · 5 min readTwo-way SMS: designing replies, keywords and opt-outs
How to design two-way SMS: numbers that can receive, keywords such as STOP and YES, routing replies to the right system and handing over to a person.
Read the article Channels · 5 min readWhat does RCS cost compared with SMS, and how do you compare them?
ZafeConnect list prices for SMS, basic RCS and rich RCS per message, how to compare cost per delivered message, and how to choose an RCS provider.
Read the article Channels · 5 min readRich media and buttons in business messaging: which channels can do what
Which channels support images, buttons and interactive elements: SMS, MMS, RCS, Apple Messages for Business and WhatsApp, what each needs, and fallback design.
Read the articlePlatforms and CPaaS
Combining channels, email, push and your own systems on one platform.
The most important features of a modern CPaaS platform: a buyer’s checklist
The most important features of a modern CPaaS platform as a checklist: API, channels and fallback, routing, delivery reports, analytics, pricing and support.
Read the article Platforms and CPaaS · 6 min readHow to plan an omnichannel customer journey and pick the channel for each step
How to plan an omnichannel customer journey: pick the channel per step for SMS, RCS, iMessage, WhatsApp, email and push, set a fallback order, consent and cost.
Read the article Platforms and CPaaS · 6 min readHow to combine transactional email and SMS notifications
How to combine transactional email and SMS: which message on which channel, timing, fallback both ways, avoiding duplicates and keeping logs in one place.
Read the article Platforms and CPaaS · 5 min readPush notifications and SMS together: when should SMS take over?
When is push enough, and when should SMS take over? Timing windows, opt-in differences and how to avoid duplicates when you combine push and SMS.
Read the articleFor developers
Webhooks, retries, integrations and a go-live checklist.
Webhooks for delivery status: design for retries and duplicates
How to build a webhook endpoint for message status: acknowledge fast, handle duplicates and out-of-order events, verify signatures and reconcile gaps.
Read the article For developers · 6 min readSMS API integration: a checklist before you go live
A practical checklist before you send real traffic through an SMS API: keys, number format, retries, rate limits, webhooks, monitoring and country tests.
Read the article For developers · 6 min readSMS and CRM: how to connect messaging to your business systems
How to connect SMS and messaging to a CRM: API or ready-made connector, webhooks, status back into the CRM, syncing opt-outs, test keys and go-live.
Read the articleChoosing a provider
What to compare and how to test a provider before you commit.
The real cost of messaging: what to compare beyond the price per message
What to compare besides the price per message: segments, billing on sent or delivered, fees, currency and VAT, failures, and how to build a fair comparison.
Read the article Choosing a provider · 6 min readHow to run a messaging provider pilot
A step-by-step plan for testing an SMS provider with real traffic: goals, countries, parallel runs, the metrics to compare and the mistakes to avoid.
Read the article Choosing a provider · 6 min read18 questions to ask an SMS gateway partner in your RFP
What to look for when you choose an SMS gateway partner: 18 questions on delivery, security, price, support, integration and exit for your RFP or procurement.
Read the article Choosing a provider · 5 min readWhat a Danish SMS provider actually means
What a Danish SMS provider means in practice: company and contract, support, data processing, sub-processors, sender rules and invoicing.
Read the article Choosing a provider · 6 min readAlternatives to the large global CPaaS providers: what to weigh
What to weigh when looking for an alternative to the large global CPaaS providers: size, contract, price, support, region, channels and switching.
Read the article Choosing a provider · 6 min readBulk SMS: how to compare price and delivery together
How to compare bulk SMS on price and delivery together: price per delivered message, route quality, delivery reports, fees, volume tiers and testing.
Read the article Choosing a provider · 5 min readPay per delivered SMS: what to ask
Pay per delivered versus pay per submitted: what “delivered” means, what to ask, and how to see fixed fees and subscriptions in the price.
Read the article Choosing a provider · 5 min readWhat to demand from support on a messaging platform
What to demand from support on a messaging platform: round-the-clock coverage, severity levels, response times, escalation, technical support and a status page.
Read the articleThese articles are general information, not legal advice. Rules differ by country and change over time.
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