This article provides a basic overview of the primary differences between SharePoint Online and SharePoint On-Premises. So let’s begin by taking a look at the different environments needed to run online vs. On Premise:
SharePoint Environments
As with any on-premise vs cloud based discussion, one of the most significant differences is the impact on internal resources. On-premise solutions require an internal IT support structure including people, hardware and software, or the use of a Managed Service Provider (MSP). Cloud based solutions reduce the dependency on internal resources and typically provide better globally deployed failover and redundancy features.
On Premises
Online
·         The SharePoint server farm is within the corporate network.
·         The IT Support team maintains the SharePoint farm and regularly applies Microsoft patches and updates.
·         On premise Active directory is used for authentication.
·         Full access to use and customize any SharePoint feature as needed.
·         Availability of Enterprise level services such as BCS, Performance Point, etc.
·         The SharePoint sites reside in the Microsoft Data Centre (MDC).
·         Microsoft applies the patch regularly.
·         Microsoft’s SLA ensures 99.9% availability.
·         Microsoft’s global network of data centers provides reduced latency and high network bandwidth.
·         Support for Client Side Object & App model.
Feature Comparisons
While the basic functionality of SharePoint remains the same, there are a number of significant feature differences between On Premises and Online:
Category
On Premises
Online
Cost Involved
Purchase/Maintain Hardware, Software licenses etc.
Annual subscriptions for Office 365 Plans billed on a per user basis.
Infrastructure deployment & maintenance
IT Support Team to deploy/manage farm, latest updates or patches not always deployed.
Microsoft manages the environment and ensures all updates and patches are deployed.
Business Continuity (BC)
Dependent on internal capabilities.
Microsoft built-in redundancy and failover for data centres, but does not provide end user backups or data recovery.
Product Features
Support for enterprise feature, Office web App (OWA) needs to be installed
Missing or limited features, pre-configured features
Customization Options
Full support for server side code and client side code, App usage from OAC and SAS
Full Support- Client Side, Limited Support-Server side, Can use Apps from OAC or SAS
Information Security
Dependent on internal capabilities.
Information in MDS meets industry-specific security standards
Compliance Standard
Dependent on internal capabilities.
Verified by third party authors
Storage needs
Expensive storage devices, Site Collection -More than 100GB, Scalable Storage Size
Cheap storage cost, Site Collection- up to 100Gb, Maximum content in single tenant -O365 plan based
Development
Full trust solution can be deployed- Features in farm solutions can have scope as wide as the site collection, web application, or whole farm Public facing website with much of customization is possible Custom “Managed Path” allowed More control can be delegated to power users
Full trust solution cannot be deployed- Only Sandbox solutions possible with scope up to the site collection level Public facing website with much of customization is not possible Custom “Managed Path” allowed More control cannot be delegated to power users and maxim privilege level is Site Collection level.
Services Support:
Services
Online
On Premises
Search
Limited access to query
Full text Query
InfoPath Form Services
Only in E3, E4 and K1 plans
Required License to use InfoPath Form Services
Claim Bases Authentication
N/A
Can use SQL , LDAP and AD authentication
Managed Accounts
N/A
Provides a Managed Account to user at access the SP Admin Services
Usage reporting and Logging
N/A
Provides LOGS and Reporting to check the exceptions and System Report.
Alternate Access Mapping
N/A
Provides a map requests where the URL of a Web request received by Internet Information Services (IIS) differs from the URL that was typed by a user
SharePoint Health Analyser
N/A
Site collection pre-upgrade health check examines a site collection and then generates a report listing ay potential upgrade issues and how to address the issues


SharePoint On Premises
Pros
Cons
Control Performance
Cost of internal resources (staff, hardware, software, etc)
Scale Up and Scale Out
Additional Geographic redundancy costs
Reduces Bandwidth requirements
Disaster Recovery dependent on internal capabilities
Fully Customizable
Scale Up/Out Cost( SW/HW)
Full Server and SQL Database
Patching Servers/farms
Migrate as Needed
Extra configurations for External Collaboration
Seamless Single Sign on with Corporate Active Directory
SharePoint Online
Pros
Cons
Uptime 99.99%
More ISP Bandwidth
Multiple Data centers
Limited Customizations
Geographically redundant
Possible Storage Costs
Shorted release cycle
Recovery SLAs
Managed Services ( SaaS)
No Server access
Pay as you go ( Low Cost )
Reduced impact on internal IT resources
Scalability
Listing of notable limitations of SharePoint Online for Enterprise
1.       Sites Types
a.       Single public facing site
b.      Multiple internal/private sites (top level is a Team Site).
*There are no web applications.  All sites must exist under a single web application using separate site collections
2.       Data Storage Limitations
a.       Tenant storage: 10 GB + 500 MB per subscribed user + additional storage purchased.  For example, if you have 10,000 users, the base storage allocation is approximately 5 Terabytes (10 GB + 500 MB * 10,000 users).
b.      Site collection: Hard limit of 100GB
c.       Overall subscription limit: 25TB
3.       External Users
Per MS: “An external user is a person who has been granted access to your SharePoint Online site, but who is not a licensed user within your organization. External users are users who are not employees, contractors, or onsite agents for either you or your affiliates.”
a.       Maximum number of external users: 10,000
b.      External users cannot create their own My Sites or One Drive Pro
c.       Cannot change their profile, edit picture or see tasks
d.      Cannot be an administrator for a site collection
e.      Cannot access search center or execute searches against “everything”
4.       Missing Features/Services in SharePoint Online (365)
5.       Missing: Central Administration
a.       Does not exist in SharePoint Online (SPO), rather there is an “SharePoint Admin Center”
Description: http://microscoff.com/wp-content/uploads/2014/02/Office365-SharePoint-Admin-Center.jpg
6.       Missing: Web Application Management / Managed Paths
a.       Starts at the Site Collection level
    1. All sites, other than the public and top level team site, must exist under the “.sharepoint.com/sites/” area
Description: http://microscoff.com/wp-content/uploads/2014/02/Office-365-Managed-Paths-Options.jpg
7.       Missing: Full Trust Solutions
a.       You can only create Sandbox and App model solutions.  3rd party solutions would need to be in this format.
8.       Missing: Search Control and Index
a.       Unable to set crawl schedules
b.      Unable to initiate crawl (default is ~5 minutes)
c.       Unable to create custom solutions against Search Index
d.      Unable to add entity extraction (custom refiners)
e.      Unable to enhance relevancy (custom ranking models)
f.        No federated search
9.       Missing: Cross site publishing
Per MS: “Cross-site publishing is a new publishing method that lets you create and maintain content in one or more authoring site collections and publish this content in one or more publishing site collections by using Search Web Parts. Cross-site publishing complements the already existing publishing method, author-in-place, where you use a single site collection to author content and make it available to readers of your site.”
10.   Missing: Content by search
(Content by search allows content to be displayed in a web part via search.  One of the top features of SP13.)
11.   Unavailable SharePoint Services
a.       Access Services 2010
b.      PerformancePoint Service
c.       PowerPoint Automation Service
d.      State Service
e.      User and Health Data Collection Service*
*(Office 365 provides separate health info in admin center)
f.        Word Automation Service
g.       Work Management Service
h.      Microsoft Foundation Subscription Settings Service
12.   Branding Limitations
Adding a custom design to the internal site “Team Site” is a bit counter intuitive.  The option to select a MasterPage is not available under “Site Settings.”  You must upload the MasterPage to the MasterPage gallery, along with a “Preview” file.  Then, you must create a “Composed” look.  From there it will be available under the “Change the Look” feature.  I hope to detail this out more in a future post.
13.   Other Notable Limitations
    1. Migration must be done4 remotely
b.      Disks cannot be shipped
c.       Cannot control upgrade schedule

BCS security concerns about opening local data up to the cloud